CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-sticky-header-enabled vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Open-source license - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-sticky-header-enabled vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"926bbb18-37e9-469f-a98d-edcab58c4a1f","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Open-source_license","wgTitle":"Open-source license","wgCurRevisionId":1277721558,"wgRevisionId":1277721558,"wgArticleId":22290,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Good articles","Articles with short description","Short description is different from Wikidata","Use mdy dates from January 2023","CS1: long volume value","Free and open-source software licenses","Terms of service","Free culture movement"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Open-source_license","wgRelevantArticleId":22290,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true, "wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":50000,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q97044024","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false, "wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","ext.tmh.player.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","mediawiki.page.media","ext.tmh.player","ext.scribunto.logs","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups", "ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.tmh.player.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.17"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/8/86/Open-source-license-chart.svg/1200px-Open-source-license-chart.svg.png"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="1200"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/8/86/Open-source-license-chart.svg/800px-Open-source-license-chart.svg.png"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="800"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/8/86/Open-source-license-chart.svg/640px-Open-source-license-chart.svg.png"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="640"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Open-source license - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Open-source_license"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Open-source_license&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Open-source_license"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Open-source_license rootpage-Open-source_license skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" title="Main menu" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li><li id="n-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages"><span>Special pages</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/?wmf_source=donate&wmf_medium=sidebar&wmf_campaign=en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Open-source+license" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Open-source+license" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/?wmf_source=donate&wmf_medium=sidebar&wmf_campaign=en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Open-source+license" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Open-source+license" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Background" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Background"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Background</span> </div> </a> <ul id="toc-Background-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Types" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Types"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Types</span> </div> </a> <button aria-controls="toc-Types-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Types subsection</span> </button> <ul id="toc-Types-sublist" class="vector-toc-list"> <li id="toc-Permissive" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Permissive"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Permissive</span> </div> </a> <ul id="toc-Permissive-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Copyleft" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Copyleft"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Copyleft</span> </div> </a> <ul id="toc-Copyleft-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Compatibility" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Compatibility"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Compatibility</span> </div> </a> <ul id="toc-Compatibility-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Enforcement" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Enforcement"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Enforcement</span> </div> </a> <ul id="toc-Enforcement-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Public_domain_software" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Public_domain_software"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Public domain software</span> </div> </a> <ul id="toc-Public_domain_software-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Use_in_proprietary_software" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Use_in_proprietary_software"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Use in proprietary software</span> </div> </a> <ul id="toc-Use_in_proprietary_software-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Open-source license</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 15 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-15" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">15 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%A7%D9%84%D8%AA%D8%B1%D8%AE%D9%8A%D8%B5_%D9%85%D9%81%D8%AA%D9%88%D8%AD_%D8%A7%D9%84%D9%85%D8%B5%D8%AF%D8%B1" title="الترخيص مفتوح المصدر – Arabic" lang="ar" hreflang="ar" data-title="الترخيص مفتوح المصدر" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%89%E0%A6%A8%E0%A7%8D%E0%A6%AE%E0%A7%81%E0%A6%95%E0%A7%8D%E0%A6%A4_%E0%A6%89%E0%A7%8E%E0%A6%B8%E0%A7%87%E0%A6%B0_%E0%A6%B2%E0%A6%BE%E0%A6%87%E0%A6%B8%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%B8" title="উন্মুক্ত উৎসের লাইসেন্স – Bangla" lang="bn" hreflang="bn" data-title="উন্মুক্ত উৎসের লাইসেন্স" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Llic%C3%A8ncia_lliure" title="Llicència lliure – Catalan" lang="ca" hreflang="ca" data-title="Llicència lliure" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Open-source_licence" title="Open-source licence – Czech" lang="cs" hreflang="cs" data-title="Open-source licence" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Licencia_de_c%C3%B3digo_abierto" title="Licencia de código abierto – Spanish" lang="es" hreflang="es" data-title="Licencia de código abierto" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%85%D8%AC%D9%88%D8%B2_%D9%85%D8%AA%D9%86%E2%80%8C%D8%A8%D8%A7%D8%B2" title="مجوز متن‌باز – Persian" lang="fa" hreflang="fa" data-title="مجوز متن‌باز" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%98%A4%ED%94%88_%EC%86%8C%EC%8A%A4_%EC%82%AC%EC%9A%A9%EA%B6%8C" title="오픈 소스 사용권 – Korean" lang="ko" hreflang="ko" data-title="오픈 소스 사용권" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Licenza_open_source" title="Licenza open source – Italian" lang="it" hreflang="it" data-title="Licenza open source" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Ny%C3%ADlt_forr%C3%A1sk%C3%B3d%C3%BA_licenc" title="Nyílt forráskódú licenc – Hungarian" lang="hu" hreflang="hu" data-title="Nyílt forráskódú licenc" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%AA%E3%83%BC%E3%83%97%E3%83%B3%E3%82%BD%E3%83%BC%E3%82%B9%E3%83%A9%E3%82%A4%E3%82%BB%E3%83%B3%E3%82%B9" title="オープンソースライセンス – Japanese" lang="ja" hreflang="ja" data-title="オープンソースライセンス" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Licen%C3%A7a_de_c%C3%B3digo_aberto" title="Licença de código aberto – Portuguese" lang="pt" hreflang="pt" data-title="Licença de código aberto" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%AA%E0%B8%B1%E0%B8%8D%E0%B8%8D%E0%B8%B2%E0%B8%AD%E0%B8%99%E0%B8%B8%E0%B8%8D%E0%B8%B2%E0%B8%95%E0%B9%82%E0%B8%AD%E0%B9%80%E0%B8%9E%E0%B8%99%E0%B8%8B%E0%B8%AD%E0%B8%A3%E0%B9%8C%E0%B8%8B" title="สัญญาอนุญาตโอเพนซอร์ซ – Thai" lang="th" hreflang="th" data-title="สัญญาอนุญาตโอเพนซอร์ซ" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9B%D1%96%D1%86%D0%B5%D0%BD%D0%B7%D1%96%D1%8F_%D0%B7_%D0%B2%D1%96%D0%B4%D0%BA%D1%80%D0%B8%D1%82%D0%B8%D0%BC_%D0%BA%D0%BE%D0%B4%D0%BE%D0%BC" title="Ліцензія з відкритим кодом – Ukrainian" lang="uk" hreflang="uk" data-title="Ліцензія з відкритим кодом" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Gi%E1%BA%A5y_ph%C3%A9p_ngu%E1%BB%93n_m%E1%BB%9F" title="Giấy phép nguồn mở – Vietnamese" lang="vi" hreflang="vi" data-title="Giấy phép nguồn mở" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E9%96%8B%E6%BA%90%E6%8E%88%E6%AC%8A" title="開源授權 – Chinese" lang="zh" hreflang="zh" data-title="開源授權" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q97044024#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Open-source_license" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Open-source_license" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Open-source_license"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Open-source_license&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Open-source_license&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Open-source_license"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Open-source_license&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Open-source_license&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Open-source_license" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Open-source_license" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Open-source_license&oldid=1277721558" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Open-source_license&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Open-source_license&id=1277721558&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FOpen-source_license"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FOpen-source_license"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Open-source_license&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Open-source_license&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q97044024" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> <div id="mw-indicator-good-star" class="mw-indicator"><div class="mw-parser-output"><span typeof="mw:File"><a href="/wiki/Wikipedia:Good_articles*" title="This is a good article. Click here for more information."><img alt="This is a good article. Click here for more information." src="//upload.wikimedia.org/wikipedia/en/thumb/9/94/Symbol_support_vote.svg/19px-Symbol_support_vote.svg.png" decoding="async" width="19" height="20" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/94/Symbol_support_vote.svg/29px-Symbol_support_vote.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/94/Symbol_support_vote.svg/39px-Symbol_support_vote.svg.png 2x" data-file-width="180" data-file-height="185" /></a></span></div></div> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><p class="mw-empty-elt"> </p> <div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Software license allowing source code to be used, modified, and shared</div> <p class="mw-empty-elt"> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Open-source-license-chart.svg" class="mw-file-description"><img alt="A pie chart displays the most commonly used open source license as Apache at 30%, MIT at 26%, GPL at 18%, BSD at 8%, LGPL at 3%, MPL at 2%, and remaining 13% as licenses with below 1% market share each." src="//upload.wikimedia.org/wikipedia/commons/thumb/8/86/Open-source-license-chart.svg/220px-Open-source-license-chart.svg.png" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/86/Open-source-license-chart.svg/330px-Open-source-license-chart.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/86/Open-source-license-chart.svg/440px-Open-source-license-chart.svg.png 2x" data-file-width="180" data-file-height="180" /></a><figcaption>Popular open source licenses include the <a href="/wiki/Apache_License" title="Apache License">Apache License</a>, the <a href="/wiki/MIT_License" title="MIT License">MIT License</a>, the <a href="/wiki/GNU_General_Public_License" title="GNU General Public License">GNU General Public License</a> (GPL), the <a href="/wiki/BSD_Licenses" class="mw-redirect" title="BSD Licenses">BSD Licenses</a>, the <a href="/wiki/GNU_Lesser_General_Public_License" title="GNU Lesser General Public License">GNU Lesser General Public License</a> (LGPL) and the <a href="/wiki/Mozilla_Public_License" title="Mozilla Public License">Mozilla Public License</a> (MPL).</figcaption></figure> <p><b>Open-source licenses</b> are <a href="/wiki/Software_license" title="Software license">software licenses</a> that allow content to be used, modified, and shared. They facilitate <a href="/wiki/Free_and_open-source_software" title="Free and open-source software">free and open-source software</a> (FOSS) development. <a href="/wiki/Intellectual_property" title="Intellectual property">Intellectual property</a> (IP) laws restrict the modification and sharing of creative works. Free and open-source licenses use these existing legal structures for an inverse purpose. They <a href="/wiki/Grant_(law)" title="Grant (law)">grant</a> the recipient the rights to use the software, examine the <a href="/wiki/Source_code" title="Source code">source code</a>, modify it, and distribute the modifications. These criteria are outlined in the <a href="/wiki/Open_Source_Definition" class="mw-redirect" title="Open Source Definition">Open Source Definition</a>. </p><p>After 1980, the United States began to treat software as a literary work covered by copyright law. <a href="/wiki/Richard_Stallman" title="Richard Stallman">Richard Stallman</a> founded the <a href="/wiki/Free_software_movement" title="Free software movement">free software movement</a> in response to the rise of <a href="/wiki/Proprietary_software" title="Proprietary software">proprietary software</a>. The term "open source" was used by the <a href="/wiki/Open_Source_Initiative" title="Open Source Initiative">Open Source Initiative</a> (OSI), founded by free software developers <a href="/wiki/Bruce_Perens" title="Bruce Perens">Bruce Perens</a> and <a href="/wiki/Eric_S._Raymond" title="Eric S. Raymond">Eric S. Raymond</a>. "Open source" emphasizes the strengths of the <a href="/wiki/Open-source_software_development" title="Open-source software development">open development model</a> rather than software freedoms. While the goals behind the terms are different, open-source licenses and <a href="/wiki/Free_software_license" class="mw-redirect" title="Free software license">free software licenses</a> describe the same type of licenses.<sup id="cite_ref-FOOTNOTEByfield2008_1-0" class="reference"><a href="#cite_note-FOOTNOTEByfield2008-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The two main categories of open-source licenses are <a href="/wiki/Permissive_software_license" title="Permissive software license">permissive</a> and <a href="/wiki/Copyleft" title="Copyleft">copyleft</a>. Both grant permission to change and distribute software. Typically, they require <a href="/wiki/Attribution_(copyright)" title="Attribution (copyright)">attribution</a> and <a href="/wiki/Software_product_liability" title="Software product liability">disclaim liability</a>. Permissive licenses come from academia. Copyleft licenses come from the free software movement. Copyleft licenses require <a href="/wiki/Derivative_works" class="mw-redirect" title="Derivative works">derivative works</a> to be distributed with the source code and under a similar license. Since the mid-2000s, courts in multiple countries have upheld the terms of both types of license. Software developers have filed cases as copyright infringement and as breaches of contract. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Background">Background</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=1" title="Edit section: Background"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/History_of_free_and_open-source_software" title="History of free and open-source software">History of free and open-source software</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><span><video id="mwe_player_0" poster="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv/220px--Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv.jpg" controls="" preload="none" data-mw-tmh="" class="mw-file-element" width="220" height="124" data-durationhint="718" data-mwtitle="Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture;_the_root_of_copyright.ogv" data-mwprovider="wikimediacommons" resource="/wiki/File:Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture;_the_root_of_copyright.ogv"><source src="//upload.wikimedia.org/wikipedia/commons/0/0c/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv" type="video/ogg; codecs="theora, vorbis"" data-width="512" data-height="288" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/0/0c/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv.360p.webm" type="video/webm; codecs="vp8, vorbis"" data-transcodekey="360p.webm" data-width="512" data-height="288" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/0/0c/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv.144p.mjpeg.mov" type="video/quicktime" data-transcodekey="144p.mjpeg.mov" data-width="256" data-height="144" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/0/0c/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv/Eben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv.240p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="240p.vp9.webm" data-width="426" data-height="240" /><track src="https://commons.wikimedia.org/w/api.php?action=timedtext&title=File%3AEben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv&lang=en&trackformat=vtt&origin=%2A" kind="subtitles" type="text/vtt" srclang="en" label="English ‪(en)‬" data-dir="ltr" /><track src="https://commons.wikimedia.org/w/api.php?action=timedtext&title=File%3AEben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv&lang=fi&trackformat=vtt&origin=%2A" kind="subtitles" type="text/vtt" srclang="fi" label="suomi ‪(fi)‬" data-dir="ltr" /><track src="https://commons.wikimedia.org/w/api.php?action=timedtext&title=File%3AEben_Moglen_-_From_the_birth_of_printing_to_industrial_culture%3B_the_root_of_copyright.ogv&lang=fr&trackformat=vtt&origin=%2A" kind="subtitles" type="text/vtt" srclang="fr" label="français ‪(fr)‬" data-dir="ltr" /></video></span><figcaption>Legal scholar <a href="/wiki/Eben_Moglen" title="Eben Moglen">Eben Moglen</a> on the history of copyright</figcaption></figure> <p><a href="/wiki/Intellectual_property" title="Intellectual property">Intellectual property</a> (IP) is a legal category that treats creative output as property, comparable to <a href="/wiki/Private_property" title="Private property">private property</a>.<sup id="cite_ref-FOOTNOTERosen200522_2-0" class="reference"><a href="#cite_note-FOOTNOTERosen200522-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Legal systems grant the owner of an IP the right to restrict access in many ways.<sup id="cite_ref-FOOTNOTERosen200522–23_3-0" class="reference"><a href="#cite_note-FOOTNOTERosen200522–23-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Owners can sell, lease, gift, or <a href="https://en.wiktionary.org/wiki/license#Verb" class="extiw" title="wikt:license">license</a> their properties.<sup id="cite_ref-FOOTNOTERosen200515_4-0" class="reference"><a href="#cite_note-FOOTNOTERosen200515-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Multiple types of IP law cover software including <a href="/wiki/Trademarks" class="mw-redirect" title="Trademarks">trademarks</a>, <a href="/wiki/Patents" class="mw-redirect" title="Patents">patents</a>, and <a href="/wiki/Copyrights" class="mw-redirect" title="Copyrights">copyrights</a>.<sup id="cite_ref-FOOTNOTERosen200515_4-1" class="reference"><a href="#cite_note-FOOTNOTERosen200515-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>Most countries, including the United States (US), have <a href="/wiki/History_of_copyright" title="History of copyright">created copyright laws</a> in line with the <a href="/wiki/Berne_Convention" title="Berne Convention">Berne Convention</a> with slight variations.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.1.2_5-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.1.2-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> These laws assign a copyright whenever a work is released in any <a href="https://en.wiktionary.org/wiki/fixed#Adjective" class="extiw" title="wikt:fixed">fixed</a> format.<sup id="cite_ref-FOOTNOTEFagundesPerzanowski2020529_6-0" class="reference"><a href="#cite_note-FOOTNOTEFagundesPerzanowski2020529-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Under US copyright law, the initial release is considered an <a href="/wiki/Original_work" class="mw-redirect" title="Original work">original work</a>.<sup id="cite_ref-FOOTNOTERosen200517_7-0" class="reference"><a href="#cite_note-FOOTNOTERosen200517-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> The creator, or their employer, holds the copyright to this original work and therefore has the exclusive right to make copies, release modified versions, distribute copies, perform publicly, or display the work publicly. Modified versions of the original work are <a href="/wiki/Derivative_works" class="mw-redirect" title="Derivative works">derivative works</a>.<sup id="cite_ref-FOOTNOTERosen200527–28_8-0" class="reference"><a href="#cite_note-FOOTNOTERosen200527–28-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> When a creator modifies an existing work, they hold the copyright to their modifications.<sup id="cite_ref-FOOTNOTERosen200528–29_9-0" class="reference"><a href="#cite_note-FOOTNOTERosen200528–29-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Unless the original work was in the public domain, a derivative work can only be distributed with the permission of every copyright holder.<sup id="cite_ref-FOOTNOTERosen200528_10-0" class="reference"><a href="#cite_note-FOOTNOTERosen200528-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>In 1980, the US government amended the law to treat software as a literary work. Software released after this point was restricted by IP laws.<sup id="cite_ref-FOOTNOTEOman2018641–642_11-0" class="reference"><a href="#cite_note-FOOTNOTEOman2018641–642-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> At that time, American <a href="/wiki/Activist" class="mw-redirect" title="Activist">activist</a> and programmer <a href="/wiki/Richard_Stallman" title="Richard Stallman">Richard Stallman</a> was working as a graduate student at the <a href="/wiki/MIT_Computer_Science_and_Artificial_Intelligence_Laboratory" title="MIT Computer Science and Artificial Intelligence Laboratory">MIT Computer Science and Artificial Intelligence Laboratory</a>. Stallman witnessed fragmentation among software developers. He blamed the spread of proprietary software and closed models of development. To push back against these trends, Stallman founded the <a href="/wiki/Free_software_movement" title="Free software movement">free software movement</a>.<sup id="cite_ref-FOOTNOTEWilliams2002ch.&nbsp;1_12-0" class="reference"><a href="#cite_note-FOOTNOTEWilliams2002ch.&nbsp;1-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> Throughout the 1980s, he started the <a href="/wiki/GNU_Project" title="GNU Project">GNU Project</a> to create a free operating system, wrote essays on freedom, founded the <a href="/wiki/Free_Software_Foundation" title="Free Software Foundation">Free Software Foundation</a> (FSF), and wrote several free software licenses.<sup id="cite_ref-FOOTNOTEWilliams2002ch.&nbsp;7_13-0" class="reference"><a href="#cite_note-FOOTNOTEWilliams2002ch.&nbsp;7-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> The FSF used existing intellectual property laws for the opposite of their intended goal of restriction. Instead of imposing restrictions, free software explicitly provided freedoms to the recipient.<sup id="cite_ref-FOOTNOTEWilliams2002ch.&nbsp;9_14-0" class="reference"><a href="#cite_note-FOOTNOTEWilliams2002ch.&nbsp;9-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Bruce_perens_2009.jpg" class="mw-file-description"><img alt="Photograph of Bruce Perens at a conference" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a6/Bruce_perens_2009.jpg/220px-Bruce_perens_2009.jpg" decoding="async" width="220" height="138" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a6/Bruce_perens_2009.jpg/330px-Bruce_perens_2009.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a6/Bruce_perens_2009.jpg/440px-Bruce_perens_2009.jpg 2x" data-file-width="2835" data-file-height="1782" /></a><figcaption><a href="/wiki/Bruce_Perens" title="Bruce Perens">Bruce Perens</a>, author of the <a href="/wiki/Open_Source_Definition" class="mw-redirect" title="Open Source Definition">Open Source Definition</a> </figcaption></figure> <p>In the 90s, the term "open source" was coined as an alternative label for free software, and specific criteria were laid out to determine which licenses covered free and open-source software.<sup id="cite_ref-FOOTNOTEGreenbaum2016sec._I.A_15-0" class="reference"><a href="#cite_note-FOOTNOTEGreenbaum2016sec._I.A-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEMaracke2019sec._2.2_16-0" class="reference"><a href="#cite_note-FOOTNOTEMaracke2019sec._2.2-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> Two active members of the free software community, <a href="/wiki/Bruce_Perens" title="Bruce Perens">Bruce Perens</a> and <a href="/wiki/Eric_S._Raymond" title="Eric S. Raymond">Eric S. Raymond</a>, founded the <a href="/wiki/Open_Source_Initiative" title="Open Source Initiative">Open Source Initiative</a> (OSI).<sup id="cite_ref-FOOTNOTECarver2005448–450_17-0" class="reference"><a href="#cite_note-FOOTNOTECarver2005448–450-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> At <a href="/wiki/Debian" title="Debian">Debian</a>, Perens had proposed the <a href="/wiki/Debian_Free_Software_Guidelines" class="mw-redirect" title="Debian Free Software Guidelines">Debian Free Software Guidelines</a> (DFSG).<sup id="cite_ref-FOOTNOTEPerens1999_18-0" class="reference"><a href="#cite_note-FOOTNOTEPerens1999-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> The DFSG were drafted to provide a more specific and objective standard for the FOSS that Debian would host in their repositories.<sup id="cite_ref-FOOTNOTEGreenbaum20161302–1303_19-0" class="reference"><a href="#cite_note-FOOTNOTEGreenbaum20161302–1303-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> The OSI adopted the DSFG and used them as the basis for their Open Source Definition.<sup id="cite_ref-FOOTNOTEGreenbaum20161304–1305_20-0" class="reference"><a href="#cite_note-FOOTNOTEGreenbaum20161304–1305-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> The Free Software Foundation maintains a rival set of criteria, the Free Software Definition.<sup id="cite_ref-FOOTNOTEGreenbaum20161305_21-0" class="reference"><a href="#cite_note-FOOTNOTEGreenbaum20161305-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> Historically, these three organizations and their sets of criteria have been the notable authorities in determining whether a license covers free and open-source software.<sup id="cite_ref-FOOTNOTEFontana20102_22-0" class="reference"><a href="#cite_note-FOOTNOTEFontana20102-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> There is significant diversity among individual licenses but little difference between the rival definitions.<sup id="cite_ref-FOOTNOTEMaracke2019sec._2.2_16-1" class="reference"><a href="#cite_note-FOOTNOTEMaracke2019sec._2.2-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> The three definitions each require that people receiving covered software must be able to use, modify, and redistribute the covered work.<sup id="cite_ref-FOOTNOTEColeman2004"Political_Agnosticism"_23-0" class="reference"><a href="#cite_note-FOOTNOTEColeman2004"Political_Agnosticism"-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p><p>Eric S. Raymond was a proponent of the term "<a href="/wiki/Open_source" title="Open source">open source</a>" over "free software". He viewed open source as more appealing to businesses and more reflective of the tangible advantages of FOSS development. One of Raymond's goals was to expand the existing <a href="/wiki/Hacker" title="Hacker">hacker</a> community to include large commercial developers.<sup id="cite_ref-FOOTNOTERaymond1999"Memes_and_Mythmaking"_24-0" class="reference"><a href="#cite_note-FOOTNOTERaymond1999"Memes_and_Mythmaking"-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> In <i><a href="/wiki/The_Cathedral_and_the_Bazaar" title="The Cathedral and the Bazaar">The Cathedral and the Bazaar</a></i>, Raymond compared open-source development to the <a href="/wiki/Bazaar" title="Bazaar">bazaar</a>, an open-air public market.<sup id="cite_ref-FOOTNOTEMeeker20202:33–3:06_25-0" class="reference"><a href="#cite_note-FOOTNOTEMeeker20202:33–3:06-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> He argued that aside from ethics, the open model provided advantages that proprietary software could not replicate.<sup id="cite_ref-FOOTNOTERaymond2001"The_Cathedral_and_the_Bazaar"_26-0" class="reference"><a href="#cite_note-FOOTNOTERaymond2001"The_Cathedral_and_the_Bazaar"-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEBrock2022sec.&nbsp;16.3.4_27-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec.&nbsp;16.3.4-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> Raymond focused heavily on <a href="/wiki/Software_prototyping" title="Software prototyping">feedback</a>, <a href="/wiki/Software_testing" title="Software testing">testing</a>, and <a href="/wiki/Bug_tracking_system" title="Bug tracking system">bug reports</a>.<sup id="cite_ref-FOOTNOTERaymond2001_28-0" class="reference"><a href="#cite_note-FOOTNOTERaymond2001-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> He contrasted the proprietary model where small pools of secretive workers carried out this work with the development of Linux where the pool of testers included potentially the entire world.<sup id="cite_ref-FOOTNOTERaymond2001"The_Social_Context_of_Open-Source_Software"_29-0" class="reference"><a href="#cite_note-FOOTNOTERaymond2001"The_Social_Context_of_Open-Source_Software"-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> He summarized this strength as "Given enough eyeballs, all bugs are shallow."<sup id="cite_ref-FOOTNOTERaymond200119_30-0" class="reference"><a href="#cite_note-FOOTNOTERaymond200119-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> The OSI succeeded in bringing open-source development to corporate developers including Sun Microsystems, <a href="/wiki/IBM" title="IBM">IBM</a>, Netscape, <a href="/wiki/Mozilla" title="Mozilla">Mozilla</a>, <a href="/wiki/The_Apache_Software_Foundation" title="The Apache Software Foundation">Apache</a>, Apple Inc., Microsoft, and Nokia. These companies released code under existing licenses and drafted their own to be approved by the OSI.<sup id="cite_ref-FOOTNOTEOnettiVerma200969_31-0" class="reference"><a href="#cite_note-FOOTNOTEOnettiVerma200969-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEHammerlyPaquinWalton1999_32-0" class="reference"><a href="#cite_note-FOOTNOTEHammerlyPaquinWalton1999-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Types">Types</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=2" title="Edit section: Types"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Comparison_of_free_and_open-source_software_licenses" title="Comparison of free and open-source software licenses">Comparison of free and open-source software licenses</a></div> <p>Open-source licenses are categorized as <a href="/wiki/Copyleft" title="Copyleft">copyleft</a> or <a href="/wiki/Permissive_software_license" title="Permissive software license">permissive</a>.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2_33-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.2-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> Copyleft licenses require derivative works to include <a href="/wiki/Source_code" title="Source code">source code</a> under a similar license. Permissive licenses do not, and therefore the code can be used within proprietary software. Copyleft can be further divided into strong and weak depending on whether they define derivative works broadly or narrowly.<sup id="cite_ref-FOOTNOTESenSubramaniamNelson2008211–212_34-0" class="reference"><a href="#cite_note-FOOTNOTESenSubramaniamNelson2008211–212-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEMeeker202016:13_35-0" class="reference"><a href="#cite_note-FOOTNOTEMeeker202016:13-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p><p>Licenses focus on copyright law, but code is also covered by other forms of IP.<sup id="cite_ref-FOOTNOTERosen200522–24_36-0" class="reference"><a href="#cite_note-FOOTNOTERosen200522–24-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> Major open-source licenses written since the late 1990s contain patent grants. These open-source patent grants cover the patents held by the developers.<sup id="cite_ref-FOOTNOTEBainSmith2022sec.&nbsp;10.4.3_37-0" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022sec.&nbsp;10.4.3-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Software_patents" class="mw-redirect" title="Software patents">Software patents</a> cover ideas and, rather than a specific implementation, cover <i>any</i> implementation of a <a href="/wiki/Patent_claim" title="Patent claim">claim</a>. Patent claims give the holder the right to exclude others from making, using, selling, or importing products based on the idea. Because patents grant the right to exclude rather than the right to create, it is possible to have a patent on an idea but still be unable to legally implement it if the <a href="/wiki/Invention" title="Invention">invention</a> relies on another patented idea. Thus, open-source patent grants can offer permission only from covered patents. They cannot guarantee that a third party has not patented any concepts embodied in the code.<sup id="cite_ref-FOOTNOTERosen200522–24_36-1" class="reference"><a href="#cite_note-FOOTNOTERosen200522–24-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> The older permissive licenses do not discuss patents directly and offer only implicit patent grants in their offers to use or sell covered material.<sup id="cite_ref-FOOTNOTEBainSmith2022sec._10.4.2_38-0" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022sec._10.4.2-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> Newer copyleft licenses and the 2004 Apache License offer explicit patent grants and limited protection from patent litigation.<sup id="cite_ref-FOOTNOTEBainSmith2022sec._10.4.4_39-0" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022sec._10.4.4-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> These <a href="/wiki/Software_patents_and_free_software" title="Software patents and free software">patent retaliation</a> clauses protect developers by terminating grants for any party who initiates a patent lawsuit regarding covered software.<sup id="cite_ref-FOOTNOTEBainSmith2022sec._10.4.4_39-1" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022sec._10.4.4-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> </p><p>Trademarks are the only form of IP not shared by free and open-source software. Trademarks on FOSS function the same as any other trademark.<sup id="cite_ref-FOOTNOTEChestek202230_40-0" class="reference"><a href="#cite_note-FOOTNOTEChestek202230-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> A trademark is a design that identifies the distinct source of a product. Because they distinguish products, the same designs can be used in different fields where there is no <a href="/wiki/Confusing_similarity" title="Confusing similarity">risk of confusing similar</a> sources.<sup id="cite_ref-FOOTNOTEChestek2022184–185_41-0" class="reference"><a href="#cite_note-FOOTNOTEChestek2022184–185-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> To give up control of a trademark would result in the loss of that trademark. Therefore, no open-source license freely offers the use of a trademark.<sup id="cite_ref-FOOTNOTERosen200538_42-0" class="reference"><a href="#cite_note-FOOTNOTERosen200538-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> </p><p>Trademark restrictions can overlap copyrights and affect material otherwise freely available.<sup id="cite_ref-FOOTNOTEJoy2022986_43-0" class="reference"><a href="#cite_note-FOOTNOTEJoy2022986-43"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> The US Supreme Court described using trademark law to restrict public domain content as "mutant copyright".<sup id="cite_ref-FOOTNOTEJoy2022989_44-0" class="reference"><a href="#cite_note-FOOTNOTEJoy2022989-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> In <i><a href="/wiki/Dastar_Corp._v._Twentieth_Century_Fox_Film_Corp." title="Dastar Corp. v. Twentieth Century Fox Film Corp.">Dastar Corp. v. Twentieth Century Fox Film Corp.</a></i>, the court "caution[ed] against misuse or over-extension of trademark" law without providing a firm decision on those mutant copyrights.<sup id="cite_ref-45" class="reference"><a href="#cite_note-45"><span class="cite-bracket">[</span>45<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEJoy2022987–988_46-0" class="reference"><a href="#cite_note-FOOTNOTEJoy2022987–988-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> Trademark overlap can leave open-source and free content projects vulnerable to a "hostile takeover" if outside parties file for trademarks on derivative works.<sup id="cite_ref-FOOTNOTEJoy20221004–1006_47-0" class="reference"><a href="#cite_note-FOOTNOTEJoy20221004–1006-47"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup> Notably, Andrey Duskin applied for trademarks on the <a href="/wiki/SCP_Foundation" title="SCP Foundation">SCP Foundation</a>, a collaborative writing project, when creating derivative works based on SCP stories.<sup id="cite_ref-FOOTNOTEJoy2022979,_1002_48-0" class="reference"><a href="#cite_note-FOOTNOTEJoy2022979,_1002-48"><span class="cite-bracket">[</span>48<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Permissive">Permissive</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=3" title="Edit section: Permissive"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Permissive_software_license" title="Permissive software license">Permissive software license</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:MIT_Dome_night1_Edit.jpg" class="mw-file-description"><img alt="M I T campus at night" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/MIT_Dome_night1_Edit.jpg/220px-MIT_Dome_night1_Edit.jpg" decoding="async" width="220" height="134" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/MIT_Dome_night1_Edit.jpg/330px-MIT_Dome_night1_Edit.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ac/MIT_Dome_night1_Edit.jpg/440px-MIT_Dome_night1_Edit.jpg 2x" data-file-width="2644" data-file-height="1610" /></a><figcaption>Permissive licenses generally originate in academic institutions like the <a href="/wiki/Massachusetts_Institute_of_Technology" title="Massachusetts Institute of Technology">Massachusetts Institute of Technology</a>.</figcaption></figure> <p><a href="/wiki/Permissive_software_license" title="Permissive software license">Permissive licenses</a>, also known as academic licenses,<sup id="cite_ref-FOOTNOTERosen200569_49-0" class="reference"><a href="#cite_note-FOOTNOTERosen200569-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> allow recipients to use, modify, and distribute software with no obligation to provide source code. Institutions created these licenses to distribute their creations to the public.<sup id="cite_ref-FOOTNOTERosen200569_49-1" class="reference"><a href="#cite_note-FOOTNOTERosen200569-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> Permissive licenses are usually short, often less than a page of text. They impose few <a href="https://en.wiktionary.org/wiki/condition#Noun" class="extiw" title="wikt:condition">conditions</a>. Most include disclaimers of warranty and obligations to <a href="/wiki/Credit_(creative_arts)" class="mw-redirect" title="Credit (creative arts)">credit</a> authors. A few include explicit provisions for patents, trademarks, and other forms of intellectual property.<sup id="cite_ref-FOOTNOTERosen2005101–102_50-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005101–102-50"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/University_of_California,_Berkeley" title="University of California, Berkeley">University of California, Berkeley</a> created the first open-source license when they began distributing their <a href="/wiki/Berkeley_Software_Distribution" title="Berkeley Software Distribution">Berkeley Software Distribution</a> (BSD) operating system. The <a href="/wiki/BSD_license" class="mw-redirect" title="BSD license">BSD license</a> and its later variations permit modification and distribution of the covered software. The <a href="/wiki/BSD_license" class="mw-redirect" title="BSD license">BSD licenses</a> brought the concept of academic freedom of ideas to computing. Early academic software authors had shared code based on implied promises. Berkeley made these concepts explicit with clear disclaimers for liability and warranty along with conditions, or <a href="https://en.wiktionary.org/wiki/clause#Noun" class="extiw" title="wikt:clause">clauses</a>, for redistribution. The original had four clauses, but subsequent versions have further reduced the restrictions. As a result, it is common to specify if the covered software uses a 2-clause or 3-clause version.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2.1.1_51-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.2.1.1-51"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEOSI2023_52-0" class="reference"><a href="#cite_note-FOOTNOTEOSI2023-52"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/Massachusetts_Institute_of_Technology" title="Massachusetts Institute of Technology">Massachusetts Institute of Technology</a> (MIT) created an academic license based on the BSD original. The <a href="/wiki/MIT_license" class="mw-redirect" title="MIT license">MIT license</a> clarified the conditions by making them more explicit.<sup id="cite_ref-FOOTNOTERosen200573–90_53-0" class="reference"><a href="#cite_note-FOOTNOTERosen200573–90-53"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup> For example, the MIT license describes the right to <a href="https://en.wiktionary.org/wiki/sublicense#English" class="extiw" title="wikt:sublicense">sublicense</a>.<sup id="cite_ref-FOOTNOTEOSI2023"The_MIT_License"_54-0" class="reference"><a href="#cite_note-FOOTNOTEOSI2023"The_MIT_License"-54"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> One of the strengths of open-source development is the continual process where developers can build on the derivative works of each other and combine their projects into collective works. Explicitly making covered code sublicensable provides a legal advantage when tracking the chain of authorship.<sup id="cite_ref-FOOTNOTERosen200573–90_53-1" class="reference"><a href="#cite_note-FOOTNOTERosen200573–90-53"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup> The BSD and MIT are template licenses that can be adapted to any project. They are widely adapted and used by many FOSS projects.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2.1.1_51-1" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.2.1.1-51"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/Apache_License" title="Apache License">Apache License</a> is more comprehensive and explicit. <a href="/wiki/The_Apache_Software_Foundation" title="The Apache Software Foundation">The Apache Software Foundation</a> wrote it for their <a href="/wiki/Apache_HTTP_Server" title="Apache HTTP Server">Apache HTTP Server</a>. Version 2, published in 2004, offers legal advantages over simple licenses and provides similar grants.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2.1.2_55-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.2.1.2-55"><span class="cite-bracket">[</span>55<span class="cite-bracket">]</span></a></sup> While the BSD and MIT licenses offer an implicit patent grant,<sup id="cite_ref-FOOTNOTEBainSmith2022sec.&nbsp;10.4.2_56-0" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022sec.&nbsp;10.4.2-56"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup> the Apache License includes a section on patents with an explicit grant from contributors.<sup id="cite_ref-FOOTNOTEOSI2023"Apache_License,_Version_2.0"_57-0" class="reference"><a href="#cite_note-FOOTNOTEOSI2023"Apache_License,_Version_2.0"-57"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> Additionally, it is one of the few permissive licenses with a patent retaliation clause.<sup id="cite_ref-FOOTNOTEBainSmith2022ch.&nbsp;10_58-0" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022ch.&nbsp;10-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup> Patent retaliation, or patent suspension, clauses take effect if a <a href="https://en.wiktionary.org/wiki/licensee#English" class="extiw" title="wikt:licensee">licensee</a> initiates <a href="/wiki/Patent_infringement" title="Patent infringement">patent infringement</a> litigation on covered code. In that situation, the patent grants are revoked. These clauses protect against <a href="/wiki/Patent_trolling" class="mw-redirect" title="Patent trolling">patent trolling</a>.<sup id="cite_ref-FOOTNOTEBainSmith2022sec.&nbsp;10.4.4_59-0" class="reference"><a href="#cite_note-FOOTNOTEBainSmith2022sec.&nbsp;10.4.4-59"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Copyleft">Copyleft</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=4" title="Edit section: Copyleft"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Copyleft" title="Copyleft">Copyleft</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:%22Copyleft_(L)%22_sticker,_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg" class="mw-file-description"><img alt="A sticker reads, "Copyleft circled letter L"." src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4e/%22Copyleft_%28L%29%22_sticker%2C_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg/220px-%22Copyleft_%28L%29%22_sticker%2C_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg" decoding="async" width="220" height="86" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4e/%22Copyleft_%28L%29%22_sticker%2C_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg/330px-%22Copyleft_%28L%29%22_sticker%2C_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4e/%22Copyleft_%28L%29%22_sticker%2C_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg/440px-%22Copyleft_%28L%29%22_sticker%2C_from_an_envelope_mailed_from_Don_Hopkins_to_Richard_Stallman_in_1984..jpg 2x" data-file-width="800" data-file-height="312" /></a><figcaption>The Copyleft sticker from an envelope Don Hopkins mailed to Richard Stallman in 1984</figcaption></figure> <p><a href="/wiki/Copyleft" title="Copyleft">Copyleft</a> licenses require <a href="/wiki/Source_code" title="Source code">source code</a> to be distributed with software and require the source code to be made available under a similar license.<sup id="cite_ref-FOOTNOTESenSubramaniamNelson2008211–212_34-1" class="reference"><a href="#cite_note-FOOTNOTESenSubramaniamNelson2008211–212-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTESt._Laurent200438–39_60-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200438–39-60"><span class="cite-bracket">[</span>60<span class="cite-bracket">]</span></a></sup> Like the permissive licenses, most copyleft licenses require attribution.<sup id="cite_ref-FOOTNOTEBallhausen201986_61-0" class="reference"><a href="#cite_note-FOOTNOTEBallhausen201986-61"><span class="cite-bracket">[</span>61<span class="cite-bracket">]</span></a></sup> Most, including the GPL, disclaim implied warranties.<sup id="cite_ref-FOOTNOTERosen2005135_62-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005135-62"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup> </p><p>Copyleft uses the restrictions of IP law—contrary to their usual purpose—to mandate that the code remain open.<sup id="cite_ref-FOOTNOTERosen2005103–106_63-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005103–106-63"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> The term and its related slogan, "All rights reversed", had been previously used in a playful manner by the <i><a href="/wiki/Principia_Discordia" title="Principia Discordia">Principia Discordia</a></i> and <a href="/wiki/Tiny_BASIC" title="Tiny BASIC">Tiny BASIC</a>; the modern usage begins with Richard Stallman's efforts to create a free operating system. In 1984, programmer <a href="/wiki/Don_Hopkins" title="Don Hopkins">Don Hopkins</a> mailed a manual to Stallman with a "Copyleft Ⓛ" sticker. Stallman, who was working on the GNU operating system, adopted the term.<sup id="cite_ref-FOOTNOTEKeats201064_64-0" class="reference"><a href="#cite_note-FOOTNOTEKeats201064-64"><span class="cite-bracket">[</span>64<span class="cite-bracket">]</span></a></sup> An early version of copyleft licensing was used for the 1985 release of <a href="/wiki/GNU_Emacs" title="GNU Emacs">GNU Emacs</a>.<sup id="cite_ref-FOOTNOTEWilliams2002ch.&nbsp;9_14-1" class="reference"><a href="#cite_note-FOOTNOTEWilliams2002ch.&nbsp;9-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-65" class="reference"><a href="#cite_note-65"><span class="cite-bracket">[</span>65<span class="cite-bracket">]</span></a></sup> The term became associated with the FSF's later reciprocal licenses, notably the <a href="/wiki/GNU_General_Public_License" title="GNU General Public License">GNU General Public License</a> (GPL).<sup id="cite_ref-FOOTNOTEKeats201063–67_66-0" class="reference"><a href="#cite_note-FOOTNOTEKeats201063–67-66"><span class="cite-bracket">[</span>66<span class="cite-bracket">]</span></a></sup> </p><p>Traditional, proprietary software licenses are written with the goal of increasing <a href="/wiki/Software_industry" title="Software industry">profit</a>, but Stallman wrote the GPL to increase the body of available free software. His reciprocal licenses offer the rights to use, modify, and distribute the work on the condition that people must release derivative works under a license offering these same freedoms. Software built on a copyleft base must come with the source code, and the source code must be available under the same or a similar license. This offers protection against proprietary software consuming code without giving back.<sup id="cite_ref-FOOTNOTERosen2005103–109_67-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005103–109-67"><span class="cite-bracket">[</span>67<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEMeeker20206:00–7:22_68-0" class="reference"><a href="#cite_note-FOOTNOTEMeeker20206:00–7:22-68"><span class="cite-bracket">[</span>68<span class="cite-bracket">]</span></a></sup> Richard Stallman stated that "the central idea of copyleft is to use copyright law, but flip it over to serve the opposite of its usual purpose: instead of a means of privatizing software, [copyright] becomes a means of keeping software free."<sup id="cite_ref-FOOTNOTEJoy2022990–992_69-0" class="reference"><a href="#cite_note-FOOTNOTEJoy2022990–992-69"><span class="cite-bracket">[</span>69<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Free_software_licenses" class="mw-redirect" title="Free software licenses">Free software licenses</a> are also open-source software licenses.<sup id="cite_ref-FOOTNOTEOnettiVerma200971_70-0" class="reference"><a href="#cite_note-FOOTNOTEOnettiVerma200971-70"><span class="cite-bracket">[</span>70<span class="cite-bracket">]</span></a></sup> The separate terms <a href="/wiki/Free_software" title="Free software">free software</a> and <a href="/wiki/Open-source_software" title="Open-source software">open-source software</a> reflect different values rather than a legal difference.<sup id="cite_ref-FOOTNOTESt._Laurent200481–83,_114_71-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200481–83,_114-71"><span class="cite-bracket">[</span>71<span class="cite-bracket">]</span></a></sup> Both movements and their formal definitions require the covered work to be made available with source code and with permission for modification and redistribution.<sup id="cite_ref-FOOTNOTEMaracke2019sec._2.2_16-2" class="reference"><a href="#cite_note-FOOTNOTEMaracke2019sec._2.2-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> There are occasional edge cases where only one of the FSF or the OSI accept a license, but the popular free software licenses are open source, including the <a href="/wiki/GPL" class="mw-redirect" title="GPL">GPL</a>.<sup id="cite_ref-FOOTNOTEBallhausen201982_72-0" class="reference"><a href="#cite_note-FOOTNOTEBallhausen201982-72"><span class="cite-bracket">[</span>72<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Mitchell_Baker_(2).jpg" class="mw-file-description"><img alt="Portrait of Mitchell Baker" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Mitchell_Baker_%282%29.jpg/220px-Mitchell_Baker_%282%29.jpg" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Mitchell_Baker_%282%29.jpg/330px-Mitchell_Baker_%282%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Mitchell_Baker_%282%29.jpg/440px-Mitchell_Baker_%282%29.jpg 2x" data-file-width="4317" data-file-height="2872" /></a><figcaption><a href="/wiki/Mitchell_Baker" title="Mitchell Baker">Mitchell Baker</a> drafted the Mozilla Public License while on Netscape's legal team.<sup id="cite_ref-FOOTNOTESt._Laurent200468,_75_73-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200468,_75-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>Practical benefits to copyleft licenses have attracted commercial developers. Corporations have used and written reciprocal licenses with a narrower scope than the GPL.<sup id="cite_ref-FOOTNOTETsai2008564–570_74-0" class="reference"><a href="#cite_note-FOOTNOTETsai2008564–570-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup> For example, Netscape drafted their own copyleft terms after rejecting permissive licenses for the Mozilla project.<sup id="cite_ref-FOOTNOTEHammerlyPaquinWalton1999_32-1" class="reference"><a href="#cite_note-FOOTNOTEHammerlyPaquinWalton1999-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> The GPL remains the most popular license of this type, but there are other significant examples. The FSF has crafted the <a href="/wiki/Lesser_General_Public_License" class="mw-redirect" title="Lesser General Public License">Lesser General Public License</a> (LGPL) for <a href="/wiki/Library_(computing)" title="Library (computing)">libraries</a>. <a href="/wiki/Mozilla" title="Mozilla">Mozilla</a> uses the <a href="/wiki/Mozilla_Public_License" title="Mozilla Public License">Mozilla Public License</a> (MPL) for their releases, including <a href="/wiki/Firefox" title="Firefox">Firefox</a>. <a href="/wiki/IBM" title="IBM">IBM</a> drafted the <a href="/wiki/Common_Public_License" title="Common Public License">Common Public License</a> (CPL) and later adopted the <a href="/wiki/Eclipse_Public_License" title="Eclipse Public License">Eclipse Public License</a> (EPL). A difference between the GPL and other reciprocal licenses is how they define derivative works covered by the reciprocal provisions. The GPL, and the <a href="/wiki/Affero_License" class="mw-redirect" title="Affero License">Affero License</a> (AGPL) based on it, use a broad scope to describe affected works. The AGPL extends the reciprocal obligation in the GPL to cover software made available over a network.<sup id="cite_ref-FOOTNOTETsai2008564–570_74-1" class="reference"><a href="#cite_note-FOOTNOTETsai2008564–570-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEHammerlyPaquinWalton1999_32-2" class="reference"><a href="#cite_note-FOOTNOTEHammerlyPaquinWalton1999-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> They are called <a href="/wiki/Copyleft#Strong_and_weak_copyleft" title="Copyleft">strong copyleft</a> in contrast to the <a href="/wiki/Copyleft#Strong_and_weak_copyleft" title="Copyleft">weaker copyleft</a> licenses often used by corporations. Weak copyleft uses narrower, explicit definitions of derivative works.<sup id="cite_ref-FOOTNOTESenSubramaniamNelson2008212–213_75-0" class="reference"><a href="#cite_note-FOOTNOTESenSubramaniamNelson2008212–213-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEMeeker202016:13_35-1" class="reference"><a href="#cite_note-FOOTNOTEMeeker202016:13-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> The MPL uses a file-based definition, the CPL and EPL use a module-based definition, and the FSF's own LGPL refers to software libraries.<sup id="cite_ref-FOOTNOTERosen2005refer_to_corresponding_chapters_76-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005refer_to_corresponding_chapters-76"><span class="cite-bracket">[</span>76<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Compatibility">Compatibility</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=5" title="Edit section: Compatibility"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/License_compatibility" title="License compatibility">License compatibility</a></div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Floss-license-slide-image.svg" class="mw-file-description"><img alt="Chart of license compatibility, full details in section." src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Floss-license-slide-image.svg/400px-Floss-license-slide-image.svg.png" decoding="async" width="400" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Floss-license-slide-image.svg/600px-Floss-license-slide-image.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Floss-license-slide-image.svg/800px-Floss-license-slide-image.svg.png 2x" data-file-width="1400" data-file-height="420" /></a><figcaption>Open-source software licenses and how they interact</figcaption></figure> <p><a href="/wiki/License_compatibility" title="License compatibility">License compatibility</a> determines how code with different licenses can be distributed together. The goal of open-source licensing is to make the work freely available, but this becomes complicated when working with multiple terminologies imposing different requirements.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.3_77-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.3-77"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup> There are many <a href="/wiki/License_proliferation" title="License proliferation">uncommonly used licenses</a> and some projects write their own <a href="/wiki/Bespoke" title="Bespoke">bespoke</a> agreements. As a result, this causes more confusion than other legal aspects. When releasing a <a href="/wiki/Collective_work" title="Collective work">collection</a> of applications, each license can be considered separately. However, when attempting to combine software, code from another project can only be in-licensed if the project uses compatible terms and conditions.<sup id="cite_ref-FOOTNOTERosen2005243–247_78-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005243–247-78"><span class="cite-bracket">[</span>78<span class="cite-bracket">]</span></a></sup> </p><p>When combining code bases, the original licenses can be maintained for separate components, and the larger work released under a compatible license.<sup id="cite_ref-FOOTNOTESt._Laurent2004159–163_79-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent2004159–163-79"><span class="cite-bracket">[</span>79<span class="cite-bracket">]</span></a></sup> This compatibility is often one-way. Public domain content can be used anywhere as there is no copyright claim, but code acquired under any almost any set of terms cannot be waved to the public domain. Permissive licenses can be used within copyleft works, but copyleft material cannot be released under a permissive license. Some weak copyleft licenses can be used under the GPL and are said to be GPL-compatible. GPL software can only be used under the GPL or AGPL.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.3_77-1" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.3-77"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup> Permissive licenses are broadly compatible because they can cover separate parts of a project. Multiple licenses including the GPL and Apache License have been revised to enhance compatibility.<sup id="cite_ref-80" class="reference"><a href="#cite_note-80"><span class="cite-bracket">[</span>80<span class="cite-bracket">]</span></a></sup> </p><p>Translation issues, ambiguity in licensing terms, and incompatibility of some licenses with the law in certain jurisdictions compound the problem of license compatibility.<sup id="cite_ref-FOOTNOTEBernelin2020100,_102_81-0" class="reference"><a href="#cite_note-FOOTNOTEBernelin2020100,_102-81"><span class="cite-bracket">[</span>81<span class="cite-bracket">]</span></a></sup> Downloading an open-source module is straightforward, but complying with the licensing terms can be more difficult.<sup id="cite_ref-FOOTNOTEOmbredanne2020105_82-0" class="reference"><a href="#cite_note-FOOTNOTEOmbredanne2020105-82"><span class="cite-bracket">[</span>82<span class="cite-bracket">]</span></a></sup> Because of the amount of software dependencies, engineers working on complex projects often rely on license management software to achieve compliance with the licensing terms of open-source components.<sup id="cite_ref-FOOTNOTEOmbredanne2020106_83-0" class="reference"><a href="#cite_note-FOOTNOTEOmbredanne2020106-83"><span class="cite-bracket">[</span>83<span class="cite-bracket">]</span></a></sup> Many open-source software files do not unambiguously state the license, increasing the difficulties of compliance.<sup id="cite_ref-FOOTNOTEOmbredanne2020105_82-1" class="reference"><a href="#cite_note-FOOTNOTEOmbredanne2020105-82"><span class="cite-bracket">[</span>82<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Enforcement">Enforcement</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=6" title="Edit section: Enforcement"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Open_source_license_litigation" title="Open source license litigation">Open source license litigation</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Harald_Welte_27C3.jpg" class="mw-file-description"><img alt="Portrait of Harald Welte" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/36/Harald_Welte_27C3.jpg/170px-Harald_Welte_27C3.jpg" decoding="async" width="170" height="255" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/36/Harald_Welte_27C3.jpg/255px-Harald_Welte_27C3.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/36/Harald_Welte_27C3.jpg/340px-Harald_Welte_27C3.jpg 2x" data-file-width="2856" data-file-height="4288" /></a><figcaption>Early legal victories by programmer <a href="/wiki/Harald_Welte" title="Harald Welte">Harald Welte</a> established a precedent for open-source software litigation in Germany.<sup id="cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.3_84-0" class="reference"><a href="#cite_note-FOOTNOTEBallhausen2022sec.&nbsp;5.3-84"><span class="cite-bracket">[</span>84<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>Free and open-source software licenses have been successfully <a href="/wiki/Open_source_license_litigation" title="Open source license litigation">enforced in civil</a> court since the mid-2000s.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.1-85"><span class="cite-bracket">[</span>85<span class="cite-bracket">]</span></a></sup> In a pair of early lawsuits—<a href="/wiki/Jacobsen_v._Katzer" title="Jacobsen v. Katzer">Jacobsen v. Katzer</a> in the United States and <a href="/wiki/Open_source_license_litigation#Welte_v._Sitecom_Germany_(2004)" title="Open source license litigation">Welte v. Sitecom</a> in Germany—defendants argued that open-source licenses were invalid.<sup id="cite_ref-86" class="reference"><a href="#cite_note-86"><span class="cite-bracket">[</span>86<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-87" class="reference"><a href="#cite_note-87"><span class="cite-bracket">[</span>87<span class="cite-bracket">]</span></a></sup> Sitecom and Katzer separately argued that the licenses were unenforceable. Both the <a href="/wiki/United_States_District_Court_for_the_Northern_District_of_California" title="United States District Court for the Northern District of California">US</a> and German courts rejected these claims. They ruled that the defendants could not have legally distributed the software if the licenses were unenforceable.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-1" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.1-85"><span class="cite-bracket">[</span>85<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.3_84-1" class="reference"><a href="#cite_note-FOOTNOTEBallhausen2022sec.&nbsp;5.3-84"><span class="cite-bracket">[</span>84<span class="cite-bracket">]</span></a></sup> </p><p>Courts have found that distributing software indicates acceptance of the license's terms.<sup id="cite_ref-FOOTNOTESmith2022106_88-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022106-88"><span class="cite-bracket">[</span>88<span class="cite-bracket">]</span></a></sup> Physical software releases can obtain the consumer's assent with notices placed on <a href="/wiki/Shrinkwrap" class="mw-redirect" title="Shrinkwrap">shrinkwrap</a>. <a href="/wiki/Online_distribution" class="mw-redirect" title="Online distribution">Online distribution</a> can use <a href="/wiki/Clickwrap" title="Clickwrap">clickwrap</a>, a digital equivalent where the user must click to accept.<sup id="cite_ref-FOOTNOTERosen2005137_89-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005137-89"><span class="cite-bracket">[</span>89<span class="cite-bracket">]</span></a></sup> Open-source software has an additional acceptance mechanism. Without permission from the copyright holder, the law prohibits redistribution.<sup id="cite_ref-FOOTNOTERosen2005138_90-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005138-90"><span class="cite-bracket">[</span>90<span class="cite-bracket">]</span></a></sup> Therefore, courts treat redistribution as acceptance of the license terms. These can include attribution provisions or source code provisions for copyleft licenses.<sup id="cite_ref-FOOTNOTERosen2005ch.&nbsp;6_91-0" class="reference"><a href="#cite_note-FOOTNOTERosen2005ch.&nbsp;6-91"><span class="cite-bracket">[</span>91<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEMeeker202017:04_92-0" class="reference"><a href="#cite_note-FOOTNOTEMeeker202017:04-92"><span class="cite-bracket">[</span>92<span class="cite-bracket">]</span></a></sup> </p><p>Developers typically achieve compliance without lawsuits. Social pressures, like the potential for community backlash, are often sufficient.<sup id="cite_ref-FOOTNOTESt._Laurent2004158–159_93-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent2004158–159-93"><span class="cite-bracket">[</span>93<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Cease_and_desist" title="Cease and desist">Cease and desist</a> letters are a common method to bring companies back into compliance, especially in Germany.<sup id="cite_ref-FOOTNOTEBallhausen2022127_94-0" class="reference"><a href="#cite_note-FOOTNOTEBallhausen2022127-94"><span class="cite-bracket">[</span>94<span class="cite-bracket">]</span></a></sup> A standard process has developed in the German legal system. FOSS developers present companies with a cease and desist letter. These letters outline how to come back into compliance from a violation. German judges can issue a court-mandated cease and desist order to unresponsive companies. Civil cases proceed if these first steps fail. The German procedural laws are clear and favorable to claimants.<sup id="cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.4_95-0" class="reference"><a href="#cite_note-FOOTNOTEBallhausen2022sec.&nbsp;5.4-95"><span class="cite-bracket">[</span>95<span class="cite-bracket">]</span></a></sup> </p><p>Uncertainties remain in how different courts will handle certain aspects of licensing.<sup id="cite_ref-FOOTNOTEWalden2022sec.&nbsp;1.1_96-0" class="reference"><a href="#cite_note-FOOTNOTEWalden2022sec.&nbsp;1.1-96"><span class="cite-bracket">[</span>96<span class="cite-bracket">]</span></a></sup> For software in general, there are debates about what can be patented and what can be copyrighted. Regarding an application programming interface (API), the <a href="/wiki/European_Court_of_Justice" title="European Court of Justice">European Court of Justice</a> noted in the 2012 <i><a href="/wiki/SAS_Institute_Inc_v_World_Programming_Ltd" title="SAS Institute Inc v World Programming Ltd">SAS Institute</a></i> case that "ideas and principles which underlie [computer program] interfaces are not protected by copyright".<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.1.3_97-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.1.3-97"><span class="cite-bracket">[</span>97<span class="cite-bracket">]</span></a></sup> In a <a href="/wiki/Google_LLC_v._Oracle_America,_Inc." title="Google LLC v. Oracle America, Inc.">similar 2021 case</a>, the US Supreme Court permitted the recreation of an API in a <a href="/wiki/Transformative_use" title="Transformative use">transformative</a> product under <a href="/wiki/Fair_use" title="Fair use">fair use</a>.<sup id="cite_ref-98" class="reference"><a href="#cite_note-98"><span class="cite-bracket">[</span>98<span class="cite-bracket">]</span></a></sup> </p><p>A long-debated subject within the FOSS community is whether open-source licenses are "bare licenses" or <a href="/wiki/Contract" title="Contract">contracts</a>.<sup id="cite_ref-FOOTNOTEWalden2022sec.&nbsp;1.1_96-1" class="reference"><a href="#cite_note-FOOTNOTEWalden2022sec.&nbsp;1.1-96"><span class="cite-bracket">[</span>96<span class="cite-bracket">]</span></a></sup> A bare license is a set of conditions under which actions otherwise restricted by IP laws are permitted.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-2" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.1-85"><span class="cite-bracket">[</span>85<span class="cite-bracket">]</span></a></sup> Under the bare license interpretation, advocated by the FSF, a case is brought to court by the copyright holder as <a href="/wiki/Copyright_infringement" title="Copyright infringement">copyright infringement</a>.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-3" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.1-85"><span class="cite-bracket">[</span>85<span class="cite-bracket">]</span></a></sup> Under the contract interpretation, a case can be brought to court by an involved party as a <a href="/wiki/Breach_of_contract" title="Breach of contract">breach of contract</a>.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.2_99-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.2-99"><span class="cite-bracket">[</span>99<span class="cite-bracket">]</span></a></sup> US and French courts have tried cases under both interpretations.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4_100-0" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.4-100"><span class="cite-bracket">[</span>100<span class="cite-bracket">]</span></a></sup> Non-profit organizations like FSF and the <a href="/wiki/Software_Freedom_Conservancy" title="Software Freedom Conservancy">Software Freedom Conservancy</a> offer to hold the rights to developers' projects to enforce compliance.<sup id="cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.4_95-1" class="reference"><a href="#cite_note-FOOTNOTEBallhausen2022sec.&nbsp;5.4-95"><span class="cite-bracket">[</span>95<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Public_domain_software">Public domain software</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=7" title="Edit section: Public domain software"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Public-domain_software" title="Public-domain software">Public-domain software</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Spacewar!-PDP-1-20070512.jpg" class="mw-file-description"><img alt="Spaceships and stars on a round monitor" src="//upload.wikimedia.org/wikipedia/commons/thumb/2/23/Spacewar%21-PDP-1-20070512.jpg/220px-Spacewar%21-PDP-1-20070512.jpg" decoding="async" width="220" height="148" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/23/Spacewar%21-PDP-1-20070512.jpg/330px-Spacewar%21-PDP-1-20070512.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/23/Spacewar%21-PDP-1-20070512.jpg/440px-Spacewar%21-PDP-1-20070512.jpg 2x" data-file-width="3916" data-file-height="2634" /></a><figcaption> Early computer programs like the pioneering video game <a href="/wiki/Spacewar!" title="Spacewar!">Spacewar!</a> are in the public domain.<sup id="cite_ref-FOOTNOTERoss2021"Spacewar:_End_of_Development"_101-0" class="reference"><a href="#cite_note-FOOTNOTERoss2021"Spacewar:_End_of_Development"-101"><span class="cite-bracket">[</span>101<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>When a copyright expires, the work enters the <a href="/wiki/Public_domain" title="Public domain">public domain</a>, and is freely available to anyone.<sup id="cite_ref-FOOTNOTERosen200536_102-0" class="reference"><a href="#cite_note-FOOTNOTERosen200536-102"><span class="cite-bracket">[</span>102<span class="cite-bracket">]</span></a></sup> Some creative works are not covered by copyright and enter directly into the public domain. In the early history of computing, this applied to software.<sup id="cite_ref-FOOTNOTEOman2018641–642_11-1" class="reference"><a href="#cite_note-FOOTNOTEOman2018641–642-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Early computer software was often given away with hardware.<sup id="cite_ref-FOOTNOTEWalden20223_103-0" class="reference"><a href="#cite_note-FOOTNOTEWalden20223-103"><span class="cite-bracket">[</span>103<span class="cite-bracket">]</span></a></sup> Developed initially at MIT, the pioneering video game <a href="/wiki/Spacewar!" title="Spacewar!">Spacewar!</a> was used to market and test the <a href="/wiki/PDP-1" title="PDP-1">PDP-1</a> computer.<sup id="cite_ref-FOOTNOTESmith201955–56_104-0" class="reference"><a href="#cite_note-FOOTNOTESmith201955–56-104"><span class="cite-bracket">[</span>104<span class="cite-bracket">]</span></a></sup> </p><p>According to attorney <a href="/wiki/Lawrence_Rosen_(attorney)" title="Lawrence Rosen (attorney)">Lawrence Rosen</a>, copyright laws were not written with the expectation that creators would place their work into the public domain. Thus intellectual property laws lack clear paths to <a href="/wiki/Waive" class="mw-redirect" title="Waive">waive</a> a copyright. Highly permissive licenses described as "public domain" may legally function as unilateral <a href="/wiki/Contracts" class="mw-redirect" title="Contracts">contracts</a> that offer something but impose no terms.<sup id="cite_ref-FOOTNOTERosen200574–77_105-0" class="reference"><a href="#cite_note-FOOTNOTERosen200574–77-105"><span class="cite-bracket">[</span>105<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTESt._Laurent200498_106-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200498-106"><span class="cite-bracket">[</span>106<span class="cite-bracket">]</span></a></sup> </p><p>A <a href="/wiki/Public-domain-equivalent_license" title="Public-domain-equivalent license">public-domain-equivalent license</a>, like the <a href="/wiki/Creative_Commons" title="Creative Commons">Creative Commons</a> CC0, provides a waiver of copyright claims into the public domain along with a <a href="/wiki/Permissive_software_license" title="Permissive software license">permissive software license</a> as a fallback. In jurisdictions that do not accept a public domain waiver, the permissive license takes effect.<sup id="cite_ref-FOOTNOTEFagundesPerzanowski2020524_107-0" class="reference"><a href="#cite_note-FOOTNOTEFagundesPerzanowski2020524-107"><span class="cite-bracket">[</span>107<span class="cite-bracket">]</span></a></sup> Public domain waivers share limitations with simple academic licenses. This creates the possibility that an outside party could attempt to control a public domain work via patent or trademark law.<sup id="cite_ref-FOOTNOTEJoy20221008–1010_108-0" class="reference"><a href="#cite_note-FOOTNOTEJoy20221008–1010-108"><span class="cite-bracket">[</span>108<span class="cite-bracket">]</span></a></sup> Public domain waivers handle warranties differently from any type of license. Even very permissive ones, like the MIT license, <a href="/wiki/Disclaim" class="mw-redirect" title="Disclaim">disclaim</a> warranty and liability. Anyone using the free software must accept this disclaimer as a condition. Because public domain content is available to everyone, the copyright waiver cannot impose a disclaimer.<sup id="cite_ref-FOOTNOTERosen200536_102-1" class="reference"><a href="#cite_note-FOOTNOTERosen200536-102"><span class="cite-bracket">[</span>102<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Use_in_proprietary_software">Use in proprietary software</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=8" title="Edit section: Use in proprietary software"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Open-source licenses allow other businesses to commercialize covered software.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.3.3_109-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.3.3-109"><span class="cite-bracket">[</span>109<span class="cite-bracket">]</span></a></sup> Work released under a permissive license can be incorporated into proprietary software.<sup id="cite_ref-FOOTNOTESt._Laurent200414_110-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200414-110"><span class="cite-bracket">[</span>110<span class="cite-bracket">]</span></a></sup> Permissive licenses permit the addition of new terms, including proprietary ones.<sup id="cite_ref-FOOTNOTESt._Laurent200422_111-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200422-111"><span class="cite-bracket">[</span>111<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEOnettiVerma200981_112-0" class="reference"><a href="#cite_note-FOOTNOTEOnettiVerma200981-112"><span class="cite-bracket">[</span>112<span class="cite-bracket">]</span></a></sup> Proprietary software has heavily integrated open-source code released under the Apache, BSD, and MIT licenses.<sup id="cite_ref-FOOTNOTESt._Laurent200430_113-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200430-113"><span class="cite-bracket">[</span>113<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Open-core_model" title="Open-core model">Open core</a> is a business model where developers release a core piece of software as open source and monetize a product containing it as proprietary software.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.4.2.3_114-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.4.2.3-114"><span class="cite-bracket">[</span>114<span class="cite-bracket">]</span></a></sup> The strong copyleft GPL is written to prevent distribution within proprietary software.<sup id="cite_ref-FOOTNOTETsai2008550_115-0" class="reference"><a href="#cite_note-FOOTNOTETsai2008550-115"><span class="cite-bracket">[</span>115<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTESt._Laurent200439_116-0" class="reference"><a href="#cite_note-FOOTNOTESt._Laurent200439-116"><span class="cite-bracket">[</span>116<span class="cite-bracket">]</span></a></sup> Weak copyleft licenses impose specific requirements on derivative works that may allow the covered code to be distributed within proprietary software in certain circumstances.<sup id="cite_ref-FOOTNOTESmith2022sec.&nbsp;3.3_77-2" class="reference"><a href="#cite_note-FOOTNOTESmith2022sec.&nbsp;3.3-77"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Cloud_computing" title="Cloud computing">Cloud computing</a> relies on free and open-source software and avoids the distribution that triggers most licenses. Cloud software is hosted rather than distributed.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.5.2_117-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.5.2-117"><span class="cite-bracket">[</span>117<span class="cite-bracket">]</span></a></sup> A vendor hosts the software online, and their end users do not have to download, access, or even know about the code in use.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.4.2.8_118-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.4.2.8-118"><span class="cite-bracket">[</span>118<span class="cite-bracket">]</span></a></sup> The copyleft <a href="/wiki/GNU_Affero_General_Public_License" title="GNU Affero General Public License">GNU Affero General Public License</a> (AGPL) is triggered when covered code is hosted or distributed.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.4.2.2_119-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.4.2.2-119"><span class="cite-bracket">[</span>119<span class="cite-bracket">]</span></a></sup> Some developers have adopted the AGPL, and others have switched to proprietary licenses with features of open-source licensing.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.5.3_120-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.5.3-120"><span class="cite-bracket">[</span>120<span class="cite-bracket">]</span></a></sup> For example, open-core developer <a href="/wiki/Elastic_NV" title="Elastic NV">Elastic</a> switched from the Apache license to the "source-available" <a href="/wiki/Server_Side_Public_License" title="Server Side Public License">Server Side Public License</a>.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.5.3.8_121-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.5.3.8-121"><span class="cite-bracket">[</span>121<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Source-available_software" title="Source-available software">Source-available software</a> comes with source code as a reference.<sup id="cite_ref-FOOTNOTEKunert2022_122-0" class="reference"><a href="#cite_note-FOOTNOTEKunert2022-122"><span class="cite-bracket">[</span>122<span class="cite-bracket">]</span></a></sup> </p><p>Since 2010, the cloud model has grown in prominence.<sup id="cite_ref-FOOTNOTEBrock2022sec._16.5.2_117-1" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.5.2-117"><span class="cite-bracket">[</span>117<span class="cite-bracket">]</span></a></sup> Developers have criticized cloud companies that profit from hosting open-source software without contributing money or code upstream, comparing the practice to <a href="/wiki/Strip_mining" class="mw-redirect" title="Strip mining">strip mining</a>.<sup id="cite_ref-FOOTNOTEWakabayashi2019_123-0" class="reference"><a href="#cite_note-FOOTNOTEWakabayashi2019-123"><span class="cite-bracket">[</span>123<span class="cite-bracket">]</span></a></sup> Cloud computing leader <a href="/wiki/Amazon_Web_Services" title="Amazon Web Services">Amazon Web Services</a> has stated they comply with licenses and act in their customers' best interests.<sup id="cite_ref-FOOTNOTEWakabayashi2019_123-1" class="reference"><a href="#cite_note-FOOTNOTEWakabayashi2019-123"><span class="cite-bracket">[</span>123<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTEBrock2022sec._16.5.3.2_124-0" class="reference"><a href="#cite_note-FOOTNOTEBrock2022sec._16.5.3.2-124"><span class="cite-bracket">[</span>124<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=9" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 30em;"> <ul><li><a href="/wiki/Beerware" title="Beerware">Beerware</a></li> <li><a href="/wiki/Comparison_of_free_and_open-source_software_licenses" title="Comparison of free and open-source software licenses">Comparison of free and open-source software licenses</a></li> <li><a href="/wiki/List_of_free-content_licenses" class="mw-redirect" title="List of free-content licenses">List of free-content licenses</a></li> <li><a href="/wiki/Multi-licensing" title="Multi-licensing">Multi-licensing</a></li> <li><a href="/wiki/Software_Composition_Analysis" class="mw-redirect" title="Software Composition Analysis">Software Composition Analysis</a></li> <li><a href="/wiki/Category:Free_and_open-source_software_licenses" title="Category:Free and open-source software licenses">List of free and open-source software licenses</a></li> <li><a href="/wiki/Category:Copyleft_software_licenses" title="Category:Copyleft software licenses">List of copyleft software licenses</a></li> <li><a href="/wiki/List_of_open-source_programming_languages" title="List of open-source programming languages">List of open-source programming languages</a></li> <li><a href="/wiki/Category:Permissive_software_licenses" title="Category:Permissive software licenses">List of permissive software licenses</a></li></ul></div> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=10" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-FOOTNOTEByfield2008-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEByfield2008_1-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFByfield2008">Byfield 2008</a>.</span> </li> <li id="cite_note-FOOTNOTERosen200522-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200522_2-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 22.</span> </li> <li id="cite_note-FOOTNOTERosen200522–23-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200522–23_3-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 22–23.</span> </li> <li id="cite_note-FOOTNOTERosen200515-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTERosen200515_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTERosen200515_4-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 15.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.1.2-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.1.2_5-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.1.2.</span> </li> <li id="cite_note-FOOTNOTEFagundesPerzanowski2020529-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEFagundesPerzanowski2020529_6-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFFagundesPerzanowski2020">Fagundes & Perzanowski 2020</a>, p. 529.</span> </li> <li id="cite_note-FOOTNOTERosen200517-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200517_7-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 17.</span> </li> <li id="cite_note-FOOTNOTERosen200527–28-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200527–28_8-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 27–28.</span> </li> <li id="cite_note-FOOTNOTERosen200528–29-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200528–29_9-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 28–29.</span> </li> <li id="cite_note-FOOTNOTERosen200528-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200528_10-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 28.</span> </li> <li id="cite_note-FOOTNOTEOman2018641–642-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEOman2018641–642_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEOman2018641–642_11-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFOman2018">Oman 2018</a>, pp. 641–642.</span> </li> <li id="cite_note-FOOTNOTEWilliams2002ch.&nbsp;1-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEWilliams2002ch.&nbsp;1_12-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFWilliams2002">Williams 2002</a>, ch. 1.</span> </li> <li id="cite_note-FOOTNOTEWilliams2002ch.&nbsp;7-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEWilliams2002ch.&nbsp;7_13-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFWilliams2002">Williams 2002</a>, ch. 7.</span> </li> <li id="cite_note-FOOTNOTEWilliams2002ch.&nbsp;9-14"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEWilliams2002ch.&nbsp;9_14-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEWilliams2002ch.&nbsp;9_14-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFWilliams2002">Williams 2002</a>, ch. 9.</span> </li> <li id="cite_note-FOOTNOTEGreenbaum2016sec._I.A-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGreenbaum2016sec._I.A_15-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGreenbaum2016">Greenbaum 2016</a>, sec. I.A.</span> </li> <li id="cite_note-FOOTNOTEMaracke2019sec._2.2-16"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEMaracke2019sec._2.2_16-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMaracke2019sec._2.2_16-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMaracke2019sec._2.2_16-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFMaracke2019">Maracke 2019</a>, sec. 2.2.</span> </li> <li id="cite_note-FOOTNOTECarver2005448–450-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECarver2005448–450_17-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCarver2005">Carver 2005</a>, pp. 448–450.</span> </li> <li id="cite_note-FOOTNOTEPerens1999-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEPerens1999_18-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFPerens1999">Perens 1999</a>.</span> </li> <li id="cite_note-FOOTNOTEGreenbaum20161302–1303-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGreenbaum20161302–1303_19-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGreenbaum2016">Greenbaum 2016</a>, pp. 1302–1303.</span> </li> <li id="cite_note-FOOTNOTEGreenbaum20161304–1305-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGreenbaum20161304–1305_20-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGreenbaum2016">Greenbaum 2016</a>, pp. 1304–1305.</span> </li> <li id="cite_note-FOOTNOTEGreenbaum20161305-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGreenbaum20161305_21-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGreenbaum2016">Greenbaum 2016</a>, p. 1305.</span> </li> <li id="cite_note-FOOTNOTEFontana20102-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEFontana20102_22-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFFontana2010">Fontana 2010</a>, p. 2.</span> </li> <li id="cite_note-FOOTNOTEColeman2004"Political_Agnosticism"-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEColeman2004"Political_Agnosticism"_23-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFColeman2004">Coleman 2004</a>, "Political Agnosticism".</span> </li> <li id="cite_note-FOOTNOTERaymond1999"Memes_and_Mythmaking"-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERaymond1999"Memes_and_Mythmaking"_24-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRaymond1999">Raymond 1999</a>, "Memes and Mythmaking".</span> </li> <li id="cite_note-FOOTNOTEMeeker20202:33–3:06-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMeeker20202:33–3:06_25-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMeeker2020">Meeker 2020</a>, 2:33–3:06.</span> </li> <li id="cite_note-FOOTNOTERaymond2001"The_Cathedral_and_the_Bazaar"-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERaymond2001"The_Cathedral_and_the_Bazaar"_26-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRaymond2001">Raymond 2001</a>, "The Cathedral and the Bazaar".</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec.&nbsp;16.3.4-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec.&nbsp;16.3.4_27-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.3.4.</span> </li> <li id="cite_note-FOOTNOTERaymond2001-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERaymond2001_28-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRaymond2001">Raymond 2001</a>.</span> </li> <li id="cite_note-FOOTNOTERaymond2001"The_Social_Context_of_Open-Source_Software"-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERaymond2001"The_Social_Context_of_Open-Source_Software"_29-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRaymond2001">Raymond 2001</a>, "The Social Context of Open-Source Software".</span> </li> <li id="cite_note-FOOTNOTERaymond200119-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERaymond200119_30-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRaymond2001">Raymond 2001</a>, p. 19.</span> </li> <li id="cite_note-FOOTNOTEOnettiVerma200969-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOnettiVerma200969_31-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOnettiVerma2009">Onetti & Verma 2009</a>, p. 69.</span> </li> <li id="cite_note-FOOTNOTEHammerlyPaquinWalton1999-32"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHammerlyPaquinWalton1999_32-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHammerlyPaquinWalton1999_32-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHammerlyPaquinWalton1999_32-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHammerlyPaquinWalton1999">Hammerly, Paquin & Walton 1999</a>.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.2-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2_33-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.2.</span> </li> <li id="cite_note-FOOTNOTESenSubramaniamNelson2008211–212-34"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTESenSubramaniamNelson2008211–212_34-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTESenSubramaniamNelson2008211–212_34-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFSenSubramaniamNelson2008">Sen, Subramaniam & Nelson 2008</a>, pp. 211–212.</span> </li> <li id="cite_note-FOOTNOTEMeeker202016:13-35"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEMeeker202016:13_35-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMeeker202016:13_35-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFMeeker2020">Meeker 2020</a>, 16:13.</span> </li> <li id="cite_note-FOOTNOTERosen200522–24-36"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTERosen200522–24_36-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTERosen200522–24_36-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 22–24.</span> </li> <li id="cite_note-FOOTNOTEBainSmith2022sec.&nbsp;10.4.3-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBainSmith2022sec.&nbsp;10.4.3_37-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBainSmith2022">Bain & Smith 2022</a>, sec. 10.4.3.</span> </li> <li id="cite_note-FOOTNOTEBainSmith2022sec._10.4.2-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBainSmith2022sec._10.4.2_38-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBainSmith2022">Bain & Smith 2022</a>, sec. 10.4.2.</span> </li> <li id="cite_note-FOOTNOTEBainSmith2022sec._10.4.4-39"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEBainSmith2022sec._10.4.4_39-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEBainSmith2022sec._10.4.4_39-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFBainSmith2022">Bain & Smith 2022</a>, sec. 10.4.4.</span> </li> <li id="cite_note-FOOTNOTEChestek202230-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEChestek202230_40-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFChestek2022">Chestek 2022</a>, p. 30.</span> </li> <li id="cite_note-FOOTNOTEChestek2022184–185-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEChestek2022184–185_41-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFChestek2022">Chestek 2022</a>, pp. 184–185.</span> </li> <li id="cite_note-FOOTNOTERosen200538-42"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200538_42-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 38.</span> </li> <li id="cite_note-FOOTNOTEJoy2022986-43"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy2022986_43-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, p. 986.</span> </li> <li id="cite_note-FOOTNOTEJoy2022989-44"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy2022989_44-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, p. 989.</span> </li> <li id="cite_note-45"><span class="mw-cite-backlink"><b><a href="#cite_ref-45">^</a></b></span> <span class="reference-text"><cite><i><a href="/wiki/Dastar_Corp._v._Twentieth_Century_Fox_Film_Corp." title="Dastar Corp. v. Twentieth Century Fox Film Corp.">Dastar Corp. v. Twentieth Century Fox Film Corp.</a></i></cite>, <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar_case?case=13445605668854417212#p34">539 U.S. 23</a>, 34 (2003).</span> </li> <li id="cite_note-FOOTNOTEJoy2022987–988-46"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy2022987–988_46-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, pp. 987–988.</span> </li> <li id="cite_note-FOOTNOTEJoy20221004–1006-47"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy20221004–1006_47-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, pp. 1004–1006.</span> </li> <li id="cite_note-FOOTNOTEJoy2022979,_1002-48"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy2022979,_1002_48-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, pp. 979, 1002.</span> </li> <li id="cite_note-FOOTNOTERosen200569-49"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTERosen200569_49-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTERosen200569_49-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 69.</span> </li> <li id="cite_note-FOOTNOTERosen2005101–102-50"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005101–102_50-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 101–102.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.2.1.1-51"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2.1.1_51-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2.1.1_51-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.2.1.1.</span> </li> <li id="cite_note-FOOTNOTEOSI2023-52"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOSI2023_52-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOSI2023">OSI 2023</a>.</span> </li> <li id="cite_note-FOOTNOTERosen200573–90-53"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTERosen200573–90_53-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTERosen200573–90_53-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 73–90.</span> </li> <li id="cite_note-FOOTNOTEOSI2023"The_MIT_License"-54"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOSI2023"The_MIT_License"_54-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOSI2023">OSI 2023</a>, "The MIT License".</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.2.1.2-55"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.2.1.2_55-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.2.1.2.</span> </li> <li id="cite_note-FOOTNOTEBainSmith2022sec.&nbsp;10.4.2-56"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBainSmith2022sec.&nbsp;10.4.2_56-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBainSmith2022">Bain & Smith 2022</a>, sec. 10.4.2.</span> </li> <li id="cite_note-FOOTNOTEOSI2023"Apache_License,_Version_2.0"-57"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOSI2023"Apache_License,_Version_2.0"_57-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOSI2023">OSI 2023</a>, "Apache License, Version 2.0".</span> </li> <li id="cite_note-FOOTNOTEBainSmith2022ch.&nbsp;10-58"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBainSmith2022ch.&nbsp;10_58-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBainSmith2022">Bain & Smith 2022</a>, ch. 10.</span> </li> <li id="cite_note-FOOTNOTEBainSmith2022sec.&nbsp;10.4.4-59"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBainSmith2022sec.&nbsp;10.4.4_59-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBainSmith2022">Bain & Smith 2022</a>, sec. 10.4.4.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200438–39-60"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200438–39_60-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, pp. 38–39.</span> </li> <li id="cite_note-FOOTNOTEBallhausen201986-61"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBallhausen201986_61-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBallhausen2019">Ballhausen 2019</a>, p. 86.</span> </li> <li id="cite_note-FOOTNOTERosen2005135-62"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005135_62-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 135.</span> </li> <li id="cite_note-FOOTNOTERosen2005103–106-63"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005103–106_63-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 103–106.</span> </li> <li id="cite_note-FOOTNOTEKeats201064-64"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEKeats201064_64-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFKeats2010">Keats 2010</a>, p. 64.</span> </li> <li id="cite_note-65"><span class="mw-cite-backlink"><b><a href="#cite_ref-65">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.tech-insider.org/free-software/research/1985/0715-b.txt">"Full Text of GNU Emacs Copying Permission Notice"</a>. 1985.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Full+Text+of+GNU+Emacs+Copying+Permission+Notice&rft.date=1985&rft_id=https%3A%2F%2Fwww.tech-insider.org%2Ffree-software%2Fresearch%2F1985%2F0715-b.txt&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEKeats201063–67-66"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEKeats201063–67_66-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFKeats2010">Keats 2010</a>, pp. 63–67.</span> </li> <li id="cite_note-FOOTNOTERosen2005103–109-67"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005103–109_67-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 103–109.</span> </li> <li id="cite_note-FOOTNOTEMeeker20206:00–7:22-68"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMeeker20206:00–7:22_68-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMeeker2020">Meeker 2020</a>, 6:00–7:22.</span> </li> <li id="cite_note-FOOTNOTEJoy2022990–992-69"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy2022990–992_69-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, pp. 990–992.</span> </li> <li id="cite_note-FOOTNOTEOnettiVerma200971-70"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOnettiVerma200971_70-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOnettiVerma2009">Onetti & Verma 2009</a>, p. 71.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200481–83,_114-71"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200481–83,_114_71-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, pp. 81–83, 114.</span> </li> <li id="cite_note-FOOTNOTEBallhausen201982-72"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBallhausen201982_72-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBallhausen2019">Ballhausen 2019</a>, p. 82.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200468,_75-73"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200468,_75_73-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, pp. 68, 75.</span> </li> <li id="cite_note-FOOTNOTETsai2008564–570-74"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTETsai2008564–570_74-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTETsai2008564–570_74-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFTsai2008">Tsai 2008</a>, pp. 564–570.</span> </li> <li id="cite_note-FOOTNOTESenSubramaniamNelson2008212–213-75"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESenSubramaniamNelson2008212–213_75-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSenSubramaniamNelson2008">Sen, Subramaniam & Nelson 2008</a>, pp. 212–213.</span> </li> <li id="cite_note-FOOTNOTERosen2005refer_to_corresponding_chapters-76"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005refer_to_corresponding_chapters_76-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, refer to corresponding chapters.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.3-77"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.3_77-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.3_77-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.3_77-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.3.</span> </li> <li id="cite_note-FOOTNOTERosen2005243–247-78"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005243–247_78-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 243–247.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent2004159–163-79"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent2004159–163_79-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, pp. 159–163.</span> </li> <li id="cite_note-80"><span class="mw-cite-backlink"><b><a href="#cite_ref-80">^</a></b></span> <span class="reference-text">See <a href="#CITEREFSmith2022">Smith 2022</a>, p. 102 for: Apache License version 2.0 in 2004, GPL version 3 in 2007, LGPL version 3 in 2007, and AGPL version 3 in 2007. See <a href="#CITEREFSmith2022">Smith 2022</a>, pp. 95–101 for: MPL version 2.0 in 2012 and EPL version 2 in 2017.</span> </li> <li id="cite_note-FOOTNOTEBernelin2020100,_102-81"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBernelin2020100,_102_81-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBernelin2020">Bernelin 2020</a>, pp. 100, 102.</span> </li> <li id="cite_note-FOOTNOTEOmbredanne2020105-82"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEOmbredanne2020105_82-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEOmbredanne2020105_82-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFOmbredanne2020">Ombredanne 2020</a>, p. 105.</span> </li> <li id="cite_note-FOOTNOTEOmbredanne2020106-83"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOmbredanne2020106_83-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOmbredanne2020">Ombredanne 2020</a>, p. 106.</span> </li> <li id="cite_note-FOOTNOTEBallhausen2022sec.&nbsp;5.3-84"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.3_84-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.3_84-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFBallhausen2022">Ballhausen 2022</a>, sec. 5.3.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.1-85"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.1_85-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.4.1.</span> </li> <li id="cite_note-86"><span class="mw-cite-backlink"><b><a href="#cite_ref-86">^</a></b></span> <span class="reference-text"><cite><i><a href="/wiki/Jacobsen_v._Katzer" title="Jacobsen v. Katzer">Jacobsen v. Katzer</a></i></cite>, <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar_case?case=17776182574171214893">535 F.3d 1373</a> (<a href="/wiki/Fed._Cir." class="mw-redirect" title="Fed. Cir.">Fed. Cir.</a> 2008).</span> </li> <li id="cite_note-87"><span class="mw-cite-backlink"><b><a href="#cite_ref-87">^</a></b></span> <span class="reference-text"><cite><i><a href="/wiki/Welte_v._Sitecom" class="mw-redirect" title="Welte v. Sitecom">Welte v. Sitecom</a></i></cite> (District Court of Munich 2004), <a rel="nofollow" class="external text" href="https://www.ifross.org/Fremdartikel/judgment_dc_munich_gpl.pdf">No. 21 O 6123/04</a>.</span> </li> <li id="cite_note-FOOTNOTESmith2022106-88"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022106_88-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, p. 106.</span> </li> <li id="cite_note-FOOTNOTERosen2005137-89"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005137_89-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 137.</span> </li> <li id="cite_note-FOOTNOTERosen2005138-90"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005138_90-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 138.</span> </li> <li id="cite_note-FOOTNOTERosen2005ch.&nbsp;6-91"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen2005ch.&nbsp;6_91-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, ch. 6.</span> </li> <li id="cite_note-FOOTNOTEMeeker202017:04-92"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMeeker202017:04_92-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMeeker2020">Meeker 2020</a>, 17:04.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent2004158–159-93"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent2004158–159_93-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, pp. 158–159.</span> </li> <li id="cite_note-FOOTNOTEBallhausen2022127-94"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBallhausen2022127_94-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBallhausen2022">Ballhausen 2022</a>, p. 127.</span> </li> <li id="cite_note-FOOTNOTEBallhausen2022sec.&nbsp;5.4-95"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.4_95-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEBallhausen2022sec.&nbsp;5.4_95-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFBallhausen2022">Ballhausen 2022</a>, sec. 5.4.</span> </li> <li id="cite_note-FOOTNOTEWalden2022sec.&nbsp;1.1-96"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEWalden2022sec.&nbsp;1.1_96-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEWalden2022sec.&nbsp;1.1_96-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFWalden2022">Walden 2022</a>, sec. 1.1.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.1.3-97"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.1.3_97-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.1.3.</span> </li> <li id="cite_note-98"><span class="mw-cite-backlink"><b><a href="#cite_ref-98">^</a></b></span> <span class="reference-text"><cite><i><a href="/wiki/Google_LLC_v._Oracle_America,_Inc." title="Google LLC v. Oracle America, Inc.">Google LLC v. Oracle America, Inc.</a></i></cite>, <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar_case?case=4050620474768552042#p1203">593 U.S.</a>, 1203 (2021).</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.4.2-99"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4.2_99-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.4.2.</span> </li> <li id="cite_note-FOOTNOTESmith2022sec.&nbsp;3.4-100"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith2022sec.&nbsp;3.4_100-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2022">Smith 2022</a>, sec. 3.4.</span> </li> <li id="cite_note-FOOTNOTERoss2021"Spacewar:_End_of_Development"-101"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERoss2021"Spacewar:_End_of_Development"_101-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRoss2021">Ross 2021</a>, "Spacewar: End of Development".</span> </li> <li id="cite_note-FOOTNOTERosen200536-102"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTERosen200536_102-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTERosen200536_102-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, p. 36.</span> </li> <li id="cite_note-FOOTNOTEWalden20223-103"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEWalden20223_103-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFWalden2022">Walden 2022</a>, p. 3.</span> </li> <li id="cite_note-FOOTNOTESmith201955–56-104"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESmith201955–56_104-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSmith2019">Smith 2019</a>, pp. 55–56.</span> </li> <li id="cite_note-FOOTNOTERosen200574–77-105"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERosen200574–77_105-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRosen2005">Rosen 2005</a>, pp. 74–77.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200498-106"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200498_106-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, p. 98.</span> </li> <li id="cite_note-FOOTNOTEFagundesPerzanowski2020524-107"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEFagundesPerzanowski2020524_107-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFFagundesPerzanowski2020">Fagundes & Perzanowski 2020</a>, p. 524.</span> </li> <li id="cite_note-FOOTNOTEJoy20221008–1010-108"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJoy20221008–1010_108-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJoy2022">Joy 2022</a>, pp. 1008–1010.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.3.3-109"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.3.3_109-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.3.3.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200414-110"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200414_110-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, p. 14.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200422-111"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200422_111-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, p. 22.</span> </li> <li id="cite_note-FOOTNOTEOnettiVerma200981-112"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEOnettiVerma200981_112-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFOnettiVerma2009">Onetti & Verma 2009</a>, p. 81.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200430-113"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200430_113-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, p. 30.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.4.2.3-114"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.4.2.3_114-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.4.2.3.</span> </li> <li id="cite_note-FOOTNOTETsai2008550-115"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETsai2008550_115-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTsai2008">Tsai 2008</a>, p. 550.</span> </li> <li id="cite_note-FOOTNOTESt._Laurent200439-116"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESt._Laurent200439_116-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSt._Laurent2004">St. Laurent 2004</a>, p. 39.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.5.2-117"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEBrock2022sec._16.5.2_117-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEBrock2022sec._16.5.2_117-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.5.2.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.4.2.8-118"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.4.2.8_118-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.4.2.8.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.4.2.2-119"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.4.2.2_119-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.4.2.2.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.5.3-120"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.5.3_120-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.5.3.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.5.3.8-121"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.5.3.8_121-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.5.3.8.</span> </li> <li id="cite_note-FOOTNOTEKunert2022-122"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEKunert2022_122-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFKunert2022">Kunert 2022</a>.</span> </li> <li id="cite_note-FOOTNOTEWakabayashi2019-123"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEWakabayashi2019_123-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEWakabayashi2019_123-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFWakabayashi2019">Wakabayashi 2019</a>.</span> </li> <li id="cite_note-FOOTNOTEBrock2022sec._16.5.3.2-124"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBrock2022sec._16.5.3.2_124-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBrock2022">Brock 2022</a>, sec. 16.5.3.2.</span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Open-source_license&action=edit&section=11" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin refbegin-columns references-column-width" style="column-width: 30em"> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBallhausen2019" class="citation journal cs1">Ballhausen, Miriam (June 2019). <a rel="nofollow" class="external text" href="https://www.computer.org/csdl/magazine/co/2019/06/08728094/1axaDABEhXy">"Free and Open Source Software Licenses Explained"</a>. <i>Computer</i>. <b>52</b> (6): <span class="nowrap">82–</span>86. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMC.2019.2907766">10.1109/MC.2019.2907766</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Computer&rft.atitle=Free+and+Open+Source+Software+Licenses+Explained&rft.volume=52&rft.issue=6&rft.pages=%3Cspan+class%3D%22nowrap%22%3E82-%3C%2Fspan%3E86&rft.date=2019-06&rft_id=info%3Adoi%2F10.1109%2FMC.2019.2907766&rft.aulast=Ballhausen&rft.aufirst=Miriam&rft_id=https%3A%2F%2Fwww.computer.org%2Fcsdl%2Fmagazine%2Fco%2F2019%2F06%2F08728094%2F1axaDABEhXy&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBernelin2020" class="citation journal cs1">Bernelin, Margo (2020). "The Compatibility of Open/Free Licences: a Legal Imbroglio". <i>International Journal of Law and Information Technology</i>. <b>28</b> (2): <span class="nowrap">93–</span>111. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Fijlit%2Feaaa010">10.1093/ijlit/eaaa010</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=International+Journal+of+Law+and+Information+Technology&rft.atitle=The+Compatibility+of+Open%2FFree+Licences%3A+a+Legal+Imbroglio&rft.volume=28&rft.issue=2&rft.pages=%3Cspan+class%3D%22nowrap%22%3E93-%3C%2Fspan%3E111&rft.date=2020&rft_id=info%3Adoi%2F10.1093%2Fijlit%2Feaaa010&rft.aulast=Bernelin&rft.aufirst=Margo&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBrock2022" class="citation book cs1">Brock, Amanda, ed. (2022). <i>Open Source Law, Policy and Practice</i> (Second ed.). <a href="/wiki/Oxford_University_Press" title="Oxford University Press">Oxford University Press</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Foso%2F9780198862345.001.0001">10.1093/oso/9780198862345.001.0001</a></span>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-19-886234-5" title="Special:BookSources/978-0-19-886234-5"><bdi>978-0-19-886234-5</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Open+Source+Law%2C+Policy+and+Practice&rft.edition=Second&rft.pub=Oxford+University+Press&rft.date=2022&rft_id=info%3Adoi%2F10.1093%2Foso%2F9780198862345.001.0001&rft.isbn=978-0-19-886234-5&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFBainSmith2022" class="citation">Bain, Malcom; Smith, P McCoy. "<a rel="nofollow" class="external text" href="https://doi.org/10.1093/oso/9780198862345.003.0010">Patents and the Defensive Response</a>". In <a href="#CITEREFBrock2022">Brock (2022)</a>.</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFBallhausen2022" class="citation">Ballhausen, Miriam. "<a rel="nofollow" class="external text" href="https://doi.org/10.1093/oso/9780198862345.003.0005">Copyright Enforcement</a>". In <a href="#CITEREFBrock2022">Brock (2022)</a>.</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFChestek2022" class="citation">Chestek, Pamela. "<a rel="nofollow" class="external text" href="https://doi.org/10.1093/oso/9780198862345.003.0009">Trademarks</a>". In <a href="#CITEREFBrock2022">Brock (2022)</a>.</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFSmith2022" class="citation">Smith, P McCoy. "<a rel="nofollow" class="external text" href="https://doi.org/10.1093/oso/9780198862345.003.0003">Copyright, Contract, and Licensing in Open Source</a>". In <a href="#CITEREFBrock2022">Brock (2022)</a>.</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFWalden2022" class="citation">Walden, Ian. "<a rel="nofollow" class="external text" href="https://doi.org/10.1093/oso/9780198862345.003.0001">Open Source as Philosophy, Methodology, and Commerce: Using Law with Attitude</a>". In <a href="#CITEREFBrock2022">Brock (2022)</a>.</span></li></ul></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFByfield2008" class="citation web cs1">Byfield, Bruce (March 4, 2008). <a rel="nofollow" class="external text" href="https://www.datamation.com/open-source/free-and-open-source-software-navigating-the-shibboleths/">"<span class="cs1-kern-left"></span>"Free" and "Open Source" Software: Navigating the Shibboleths"</a>. <i>Datamation</i><span class="reference-accessdate">. Retrieved <span class="nowrap">June 6,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Datamation&rft.atitle=%22Free%22+and+%22Open+Source%22+Software%3A+Navigating+the+Shibboleths&rft.date=2008-03-04&rft.aulast=Byfield&rft.aufirst=Bruce&rft_id=https%3A%2F%2Fwww.datamation.com%2Fopen-source%2Ffree-and-open-source-software-navigating-the-shibboleths%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCarver2005" class="citation journal cs1">Carver, Brian W. (2005). <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/24117523">"Share and Share Alike: Understanding and Enforcing Open Source and Free Software Licenses"</a>. <i>Berkeley Technology Law Journal</i>. <b>20</b> (1): <span class="nowrap">443–</span>481. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1086-3818">1086-3818</a>. <a href="/wiki/JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/24117523">24117523</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Berkeley+Technology+Law+Journal&rft.atitle=Share+and+Share+Alike%3A+Understanding+and+Enforcing+Open+Source+and+Free+Software+Licenses&rft.volume=20&rft.issue=1&rft.pages=%3Cspan+class%3D%22nowrap%22%3E443-%3C%2Fspan%3E481&rft.date=2005&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F24117523%23id-name%3DJSTOR&rft.issn=1086-3818&rft.aulast=Carver&rft.aufirst=Brian+W.&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F24117523&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFColeman2004" class="citation journal cs1">Coleman, Gabriella (2004). <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/3318232">"The Political Agnosticism of Free and Open Source Software and the Inadvertent Politics of Contrast"</a>. <i>Anthropological Quarterly</i>. <b>77</b> (3): <span class="nowrap">507–</span>519. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1353%2Fanq.2004.0035">10.1353/anq.2004.0035</a>. <a href="/wiki/Hdl_(identifier)" class="mw-redirect" title="Hdl (identifier)">hdl</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://hdl.handle.net/10524%2F1583">10524/1583</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0003-5491">0003-5491</a>. <a href="/wiki/JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/3318232">3318232</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Anthropological+Quarterly&rft.atitle=The+Political+Agnosticism+of+Free+and+Open+Source+Software+and+the+Inadvertent+Politics+of+Contrast&rft.volume=77&rft.issue=3&rft.pages=%3Cspan+class%3D%22nowrap%22%3E507-%3C%2Fspan%3E519&rft.date=2004&rft_id=info%3Ahdl%2F10524%2F1583&rft.issn=0003-5491&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F3318232%23id-name%3DJSTOR&rft_id=info%3Adoi%2F10.1353%2Fanq.2004.0035&rft.aulast=Coleman&rft.aufirst=Gabriella&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F3318232&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDiBonaStoneOckman1999" class="citation book cs1">DiBona, Chris; Stone, Mark; Ockman, Sam, eds. (1999). <a rel="nofollow" class="external text" href="https://www.oreilly.com/openbook/opensources/book/"><i>Open Sources: Voices from the Open Source Revolution</i></a>. Sebastopol, California: <a href="/wiki/O%27Reilly_Media" title="O'Reilly Media">O'Reilly Media</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230127172901/https://www.oreilly.com/openbook/opensources/book/">Archived</a> from the original on January 27, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">January 21,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Open+Sources%3A+Voices+from+the+Open+Source+Revolution&rft.place=Sebastopol%2C+California&rft.pub=O%27Reilly+Media&rft.date=1999&rft_id=https%3A%2F%2Fwww.oreilly.com%2Fopenbook%2Fopensources%2Fbook%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFHammerlyPaquinWalton1999" class="citation">Hammerly, Jim; Paquin, Tom; Walton, Susan. "<a rel="nofollow" class="external text" href="https://www.oreilly.com/openbook/opensources/book/netrev.html">Freeing the Source: The Story of Mozilla</a>". In <a href="#CITEREFDiBonaStoneOckman1999">DiBona, Stone & Ockman (1999)</a>.</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFPerens1999" class="citation">Perens, Bruce. "<a rel="nofollow" class="external text" href="https://www.oreilly.com/openbook/opensources/book/perens.html">The Open Source Definition</a>". In <a href="#CITEREFDiBonaStoneOckman1999">DiBona, Stone & Ockman (1999)</a>.</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><span id="CITEREFRaymond1999" class="citation">Raymond, Eric S. "<a rel="nofollow" class="external text" href="https://www.oreilly.com/openbook/opensources/book/raymond2.html">The Revenge of the Hackers</a>". In <a href="#CITEREFDiBonaStoneOckman1999">DiBona, Stone & Ockman (1999)</a>.</span></li></ul></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFagundesPerzanowski2020" class="citation journal cs1">Fagundes, Dave; Perzanowski, Aaron (November 2020). "Abandoning Copyright". <i>William & Mary Law Review</i>. <b>62</b> (2): <span class="nowrap">487–</span>569.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=William+%26+Mary+Law+Review&rft.atitle=Abandoning+Copyright&rft.volume=62&rft.issue=2&rft.pages=%3Cspan+class%3D%22nowrap%22%3E487-%3C%2Fspan%3E569&rft.date=2020-11&rft.aulast=Fagundes&rft.aufirst=Dave&rft.au=Perzanowski%2C+Aaron&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFontana2010" class="citation journal cs1">Fontana, Richard E. (April 2010). "Open Source License Enforcement and Compliance". <i>The Computer and Internet Lawyer</i>. <b>27</b> (4). Aspen.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Computer+and+Internet+Lawyer&rft.atitle=Open+Source+License+Enforcement+and+Compliance&rft.volume=27&rft.issue=4&rft.date=2010-04&rft.aulast=Fontana&rft.aufirst=Richard+E.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGreenbaum2016" class="citation journal cs1">Greenbaum, Eli (April 2016). <a rel="nofollow" class="external text" href="http://cardozolawreview.com/wp-content/uploads/2018/08/GREENBAUM.37.4.pdf">"The Non-Discrimination Principle in Open Source Licensing"</a> <span class="cs1-format">(PDF)</span>. <i>Cardoza Law Review</i>. <b>37</b> (4).</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Cardoza+Law+Review&rft.atitle=The+Non-Discrimination+Principle+in+Open+Source+Licensing&rft.volume=37&rft.issue=4&rft.date=2016-04&rft.aulast=Greenbaum&rft.aufirst=Eli&rft_id=http%3A%2F%2Fcardozolawreview.com%2Fwp-content%2Fuploads%2F2018%2F08%2FGREENBAUM.37.4.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJoy2022" class="citation journal cs1">Joy, Reagan (2022). "The Tragedy of the Creative Commons: An Analysis of How Overlapping Intellectual Property Rights Undermine the Use of Permissive Licensing". <i>Case Western Reserve Law Review</i>. <b>72</b> (4): <span class="nowrap">977–</span>1013.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Case+Western+Reserve+Law+Review&rft.atitle=The+Tragedy+of+the+Creative+Commons%3A+An+Analysis+of+How+Overlapping+Intellectual+Property+Rights+Undermine+the+Use+of+Permissive+Licensing&rft.volume=72&rft.issue=4&rft.pages=%3Cspan+class%3D%22nowrap%22%3E977-%3C%2Fspan%3E1013&rft.date=2022&rft.aulast=Joy&rft.aufirst=Reagan&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKeats2010" class="citation book cs1">Keats, Jonathon (2010). <a rel="nofollow" class="external text" href="https://doi.org/10.1093/oso/9780195398540.003.0017"><i>Virtual Words: Language on the Edge of Science and Technology</i></a>. <a href="/wiki/Oxford_University_Press" title="Oxford University Press">Oxford University Press</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Foso%2F9780195398540.003.0017">10.1093/oso/9780195398540.003.0017</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-19-539854-0" title="Special:BookSources/978-0-19-539854-0"><bdi>978-0-19-539854-0</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230326192756/https://academic.oup.com/book/40770/chapter-abstract/348692229?redirectedFrom=fulltext">Archived</a> from the original on March 26, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">January 28,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Virtual+Words%3A+Language+on+the+Edge+of+Science+and+Technology&rft.pub=Oxford+University+Press&rft.date=2010&rft_id=info%3Adoi%2F10.1093%2Foso%2F9780195398540.003.0017&rft.isbn=978-0-19-539854-0&rft.aulast=Keats&rft.aufirst=Jonathon&rft_id=https%3A%2F%2Fdoi.org%2F10.1093%2Foso%2F9780195398540.003.0017&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKunert2022" class="citation news cs1">Kunert, Paul (September 8, 2022). <a rel="nofollow" class="external text" href="https://www.theregister.com/2022/09/08/open_source_biz_sick_of/">"Open Source Biz Shifts Akka to Business Source License"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221031061942/https://www.theregister.com/2022/09/08/open_source_biz_sick_of/">Archived</a> from the original on October 31, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">January 25,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Open+Source+Biz+Shifts+Akka+to+Business+Source+License&rft.date=2022-09-08&rft.aulast=Kunert&rft.aufirst=Paul&rft_id=https%3A%2F%2Fwww.theregister.com%2F2022%2F09%2F08%2Fopen_source_biz_sick_of%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMaracke2019" class="citation journal cs1">Maracke, Catharina (July 2019). <a rel="nofollow" class="external text" href="https://doi.org/10.1111%2Fjwip.12114">"Free and Open Source Software and FRAND-Based Patent Licenses: How to Mediate Between Standard Essential Patent and Free and Open Source Software"</a>. <i>The Journal of World Intellectual Property</i>. <b>22</b> (<span class="nowrap">3–</span>4): <span class="nowrap">78–</span>102. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1111%2Fjwip.12114">10.1111/jwip.12114</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Journal+of+World+Intellectual+Property&rft.atitle=Free+and+Open+Source+Software+and+FRAND-Based+Patent+Licenses%3A+How+to+Mediate+Between+Standard+Essential+Patent+and+Free+and+Open+Source+Software&rft.volume=22&rft.issue=%3Cspan+class%3D%22nowrap%22%3E3%E2%80%93%3C%2Fspan%3E4&rft.pages=%3Cspan+class%3D%22nowrap%22%3E78-%3C%2Fspan%3E102&rft.date=2019-07&rft_id=info%3Adoi%2F10.1111%2Fjwip.12114&rft.aulast=Maracke&rft.aufirst=Catharina&rft_id=https%3A%2F%2Fdoi.org%2F10.1111%252Fjwip.12114&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMeeker2020" class="citation audio-visual cs1">Meeker, Heather (January 2020). <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=gF4b1TA5Q5w&list=PLAVikl6VpxPeBtplWOnfzNmiUz529AYAy"><i>Open Source Software Licensing Basics for Corporate Users</i></a>. <i>Open Source Software Licensing</i><span class="reference-accessdate">. Retrieved <span class="nowrap">December 7,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Open+Source+Software+Licensing+Basics+for+Corporate+Users&rft.date=2020-01&rft.aulast=Meeker&rft.aufirst=Heather&rft_id=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DgF4b1TA5Q5w%26list%3DPLAVikl6VpxPeBtplWOnfzNmiUz529AYAy&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOman2018" class="citation journal cs1">Oman, Ralph (Spring 2018). "Computer Software as Copyrightable Subject Matter: Oracle V. Google, Legislative Intent, and the Scope of Rights in Digital Works". <i>Harvard Journal of Law & Technology</i>. <b>31</b> (2): <span class="nowrap">639–</span>652.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Harvard+Journal+of+Law+%26+Technology&rft.atitle=Computer+Software+as+Copyrightable+Subject+Matter%3A+Oracle+V.+Google%2C+Legislative+Intent%2C+and+the+Scope+of+Rights+in+Digital+Works&rft.ssn=spring&rft.volume=31&rft.issue=2&rft.pages=%3Cspan+class%3D%22nowrap%22%3E639-%3C%2Fspan%3E652&rft.date=2018&rft.aulast=Oman&rft.aufirst=Ralph&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOmbredanne2020" class="citation journal cs1">Ombredanne, Philippe (2020). "Free and Open Source Software License Compliance: Tools for Software Composition Analysis". <i>Computer</i>. <b>53</b> (10): <span class="nowrap">105–</span>109. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMC.2020.3011082">10.1109/MC.2020.3011082</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Computer&rft.atitle=Free+and+Open+Source+Software+License+Compliance%3A+Tools+for+Software+Composition+Analysis&rft.volume=53&rft.issue=10&rft.pages=%3Cspan+class%3D%22nowrap%22%3E105-%3C%2Fspan%3E109&rft.date=2020&rft_id=info%3Adoi%2F10.1109%2FMC.2020.3011082&rft.aulast=Ombredanne&rft.aufirst=Philippe&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOnettiVerma2009" class="citation journal cs1">Onetti, Alberto; Verma, Sameer (May 1, 2009). "Open Source Licensing and Business Models". <i>ICFAI Journal of Knowledge Management</i>. <b>7</b> (1): <span class="nowrap">68–</span>94.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=ICFAI+Journal+of+Knowledge+Management&rft.atitle=Open+Source+Licensing+and+Business+Models&rft.volume=7&rft.issue=1&rft.pages=%3Cspan+class%3D%22nowrap%22%3E68-%3C%2Fspan%3E94&rft.date=2009-05-01&rft.aulast=Onetti&rft.aufirst=Alberto&rft.au=Verma%2C+Sameer&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOSI2023" class="citation web cs1">OSI (February 2023). <a rel="nofollow" class="external text" href="https://opensource.org/licenses/">"OSI Approved Licenses"</a>. <i>opensource.org</i>. Open Source Initiative<span class="reference-accessdate">. Retrieved <span class="nowrap">December 23,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=opensource.org&rft.atitle=OSI+Approved+Licenses&rft.date=2023-02&rft.au=OSI&rft_id=https%3A%2F%2Fopensource.org%2Flicenses%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRaymond2001" class="citation book cs1">Raymond, Eric S. (2001). <a rel="nofollow" class="external text" href="http://www.catb.org/~esr/writings/cathedral-bazaar/cathedral-bazaar/"><i>The Cathedral & the Bazaar: Musings on Linux and Open Source by an Accidental Revolutionary</i></a> (Revised ed.). Sebastopol, California: <a href="/wiki/O%27Reilly_Media" title="O'Reilly Media">O'Reilly Media</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-596-00108-7" title="Special:BookSources/978-0-596-00108-7"><bdi>978-0-596-00108-7</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20030424100429/http://www.catb.org/~esr/writings/cathedral-bazaar/cathedral-bazaar/">Archived</a> from the original on April 24, 2003<span class="reference-accessdate">. Retrieved <span class="nowrap">January 28,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Cathedral+%26+the+Bazaar%3A+Musings+on+Linux+and+Open+Source+by+an+Accidental+Revolutionary&rft.place=Sebastopol%2C+California&rft.edition=Revised&rft.pub=O%27Reilly+Media&rft.date=2001&rft.isbn=978-0-596-00108-7&rft.aulast=Raymond&rft.aufirst=Eric+S.&rft_id=http%3A%2F%2Fwww.catb.org%2F~esr%2Fwritings%2Fcathedral-bazaar%2Fcathedral-bazaar%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRosen2005" class="citation book cs1">Rosen, Lawrence (2005). <a rel="nofollow" class="external text" href="https://www.rosenlaw.com/oslbook.htm"><i>Open Source Licensing: Software Freedom and Intellectual Property Law</i></a> (Paperback ed.). Upper Saddle River, NJ: <a href="/wiki/Prentice_Hall" title="Prentice Hall">Prentice Hall</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-13-148787-1" title="Special:BookSources/978-0-13-148787-1"><bdi>978-0-13-148787-1</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221219063515/https://rosenlaw.com/open-source-licensing-software-freedom-and-intellectual-property-law/">Archived</a> from the original on December 19, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">January 21,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Open+Source+Licensing%3A+Software+Freedom+and+Intellectual+Property+Law&rft.place=Upper+Saddle+River%2C+NJ&rft.edition=Paperback&rft.pub=Prentice+Hall&rft.date=2005&rft.isbn=978-0-13-148787-1&rft.aulast=Rosen&rft.aufirst=Lawrence&rft_id=https%3A%2F%2Fwww.rosenlaw.com%2Foslbook.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRoss2021" class="citation web cs1">Ross, Heather (January 4, 2021). <a rel="nofollow" class="external text" href="https://history-computer.com/spacewar-guide/">"Spacewar - Guide, History, Origin and More"</a>. <i>History-Computer</i><span class="reference-accessdate">. Retrieved <span class="nowrap">December 23,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=History-Computer&rft.atitle=Spacewar+-+Guide%2C+History%2C+Origin+and+More&rft.date=2021-01-04&rft.aulast=Ross&rft.aufirst=Heather&rft_id=https%3A%2F%2Fhistory-computer.com%2Fspacewar-guide%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSenSubramaniamNelson2008" class="citation journal cs1">Sen, Ravi; Subramaniam, Chandrasekar; Nelson, Matthew L. (Winter 2008). "Determinants of the Choice of Open Source Software License". <i>Journal of Management Information Systems</i>. <b>25</b> (3): <span class="nowrap">207–</span>239. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.2753%2FMIS0742-1222250306">10.2753/MIS0742-1222250306</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Management+Information+Systems&rft.atitle=Determinants+of+the+Choice+of+Open+Source+Software+License&rft.ssn=winter&rft.volume=25&rft.issue=3&rft.pages=%3Cspan+class%3D%22nowrap%22%3E207-%3C%2Fspan%3E239&rft.date=2008&rft_id=info%3Adoi%2F10.2753%2FMIS0742-1222250306&rft.aulast=Sen&rft.aufirst=Ravi&rft.au=Subramaniam%2C+Chandrasekar&rft.au=Nelson%2C+Matthew+L.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSmith2019" class="citation book cs1 cs1-prop-long-vol">Smith, Alexander (2019). <i>They Create Worlds: The Story of the People and Companies That Shaped the Video Game Industry</i>. Vol. 1: 1971 – 1982. Boca Raton, Florida: <a href="/wiki/CRC_Press" title="CRC Press">CRC Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-138-38990-8" title="Special:BookSources/978-1-138-38990-8"><bdi>978-1-138-38990-8</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=They+Create+Worlds%3A+The+Story+of+the+People+and+Companies+That+Shaped+the+Video+Game+Industry&rft.place=Boca+Raton%2C+Florida&rft.pub=CRC+Press&rft.date=2019&rft.isbn=978-1-138-38990-8&rft.aulast=Smith&rft.aufirst=Alexander&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSt._Laurent2004" class="citation book cs1">St. Laurent, Andrew M. (2004). <a rel="nofollow" class="external text" href="https://freecomputerbooks.com/Understanding-Open-Source-and-Free-Software-Licensing.html"><i>Understanding Open Source and Free Software Licensing</i></a>. Sebastopol, California: <a href="/wiki/O%27Reilly_Media" title="O'Reilly Media">O'Reilly Media</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0596005818" title="Special:BookSources/978-0596005818"><bdi>978-0596005818</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Understanding+Open+Source+and+Free+Software+Licensing&rft.place=Sebastopol%2C+California&rft.pub=O%27Reilly+Media&rft.date=2004&rft.isbn=978-0596005818&rft.aulast=St.+Laurent&rft.aufirst=Andrew+M.&rft_id=https%3A%2F%2Ffreecomputerbooks.com%2FUnderstanding-Open-Source-and-Free-Software-Licensing.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTsai2008" class="citation journal cs1">Tsai, John (2008). "For Better or Worse: Introducing the Gnu General Public License Version 3". <i>Berkeley Technology Law Journal</i>. <b>23</b> (1): <span class="nowrap">547–</span>581.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Berkeley+Technology+Law+Journal&rft.atitle=For+Better+or+Worse%3A+Introducing+the+Gnu+General+Public+License+Version+3&rft.volume=23&rft.issue=1&rft.pages=%3Cspan+class%3D%22nowrap%22%3E547-%3C%2Fspan%3E581&rft.date=2008&rft.aulast=Tsai&rft.aufirst=John&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWakabayashi2019" class="citation news cs1">Wakabayashi, Daisuke (December 15, 2019). <a rel="nofollow" class="external text" href="https://archive.today/20231030070154/https://www.nytimes.com/2019/12/15/technology/amazon-aws-cloud-competition.html">"Prime Leverage: How Amazon Wields Power in the Technology World"</a>. <i>The New York Times</i>. Archived from <a rel="nofollow" class="external text" href="https://www.nytimes.com/2019/12/15/technology/amazon-aws-cloud-competition.html">the original</a> on October 30, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">May 24,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=Prime+Leverage%3A+How+Amazon+Wields+Power+in+the+Technology+World&rft.date=2019-12-15&rft.aulast=Wakabayashi&rft.aufirst=Daisuke&rft_id=https%3A%2F%2Fwww.nytimes.com%2F2019%2F12%2F15%2Ftechnology%2Famazon-aws-cloud-competition.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWilliams2002" class="citation book cs1">Williams, Sam (2002). <a rel="nofollow" class="external text" href="https://www.oreilly.com/openbook/freedom/"><i>Free as in Freedom: Richard Stallman's Crusade for Free Software</i></a> (First ed.). Sebastopol, California : Farnham: <a href="/wiki/O%27Reilly_Media" title="O'Reilly Media">O'Reilly Media</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-596-00287-9" title="Special:BookSources/978-0-596-00287-9"><bdi>978-0-596-00287-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230207051646/https://en.wikisource.org/wiki/Free_as_in_Freedom_(2002)">Archived</a> from the original on February 7, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">February 6,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Free+as+in+Freedom%3A+Richard+Stallman%27s+Crusade+for+Free+Software&rft.place=Sebastopol%2C+California+%3A+Farnham&rft.edition=First&rft.pub=O%27Reilly+Media&rft.date=2002&rft.isbn=978-0-596-00287-9&rft.aulast=Williams&rft.aufirst=Sam&rft_id=https%3A%2F%2Fwww.oreilly.com%2Fopenbook%2Ffreedom%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpen-source+license" class="Z3988"></span></li></ul> </div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Software_distribution163" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Software_distribution" title="Template:Software distribution"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Software_distribution" title="Template talk:Software distribution"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Software_distribution" title="Special:EditPage/Template:Software distribution"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Software_distribution163" style="font-size:114%;margin:0 4em"><a href="/wiki/Software_distribution" title="Software distribution">Software distribution</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Software_license" title="Software license">Licenses</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Beerware" title="Beerware">Beerware</a></li> <li><a href="/wiki/Floating_licensing" title="Floating licensing">Floating licensing</a></li> <li><a href="/wiki/Free_and_open-source_software" title="Free and open-source software">Free and open-source</a> <ul><li><a href="/wiki/Free_software" title="Free software">Free</a></li> <li><a href="/wiki/Open-source_software" title="Open-source software">Open source</a></li></ul></li> <li><a href="/wiki/Freely_redistributable_software" title="Freely redistributable software">Freely redistributable</a></li> <li><a href="/wiki/License-free_software" title="License-free software">License-free</a></li> <li><a href="/wiki/Proprietary_software" title="Proprietary software">Proprietary</a></li> <li><a href="/wiki/Public-domain_software" title="Public-domain software">Public domain</a></li> <li><a href="/wiki/Source-available_software" title="Source-available software">Source-available</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Compensation models</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Adware" title="Adware">Adware</a></li> <li><a href="/wiki/Commercial_software" title="Commercial software">Commercial software</a> <ul><li><a href="/wiki/Retail_software" title="Retail software">Retail software</a></li></ul></li> <li><a href="/wiki/Crippleware" title="Crippleware">Crippleware</a></li> <li><a href="/wiki/Crowdfunding" title="Crowdfunding">Crowdfunding</a></li> <li><a href="/wiki/Freemium" title="Freemium">Freemium</a></li> <li><a href="/wiki/Freeware" title="Freeware">Freeware</a></li> <li><a href="/wiki/Pay_what_you_want" title="Pay what you want">Pay what you want</a> <ul><li><a href="/wiki/Careware" title="Careware">Careware</a></li> <li><a href="/wiki/Donationware" title="Donationware">Donationware</a></li></ul></li> <li><a href="/wiki/Open-core_model" title="Open-core model">Open-core model</a></li> <li><a href="/wiki/Postcardware" class="mw-redirect" title="Postcardware">Postcardware</a></li> <li><a href="/wiki/Shareware" title="Shareware">Shareware</a> <ul><li><a href="/wiki/Nagware" class="mw-redirect" title="Nagware">Nagware</a></li></ul></li> <li><a href="/wiki/Trialware" class="mw-redirect" title="Trialware">Trialware</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Delivery methods</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Digital_distribution" title="Digital distribution">Digital distribution</a></li> <li><a href="/wiki/File_sharing" title="File sharing">File sharing</a></li> <li><a href="/wiki/On-premises_software" title="On-premises software">On-premises</a></li> <li><a href="/wiki/Pre-installed_software" title="Pre-installed software">Pre-installed</a></li> <li><a href="/wiki/Product_bundling" title="Product bundling">Product bundling</a></li> <li><a href="/wiki/Retail_software" title="Retail software">Retail software</a></li> <li><a href="/wiki/Sneakernet" title="Sneakernet">Sneakernet</a></li> <li><a href="/wiki/Software_as_a_service" title="Software as a service">Software as a service</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Deceptive and/or illicit</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Unwanted_software_bundling" class="mw-redirect" title="Unwanted software bundling">Unwanted software bundling</a></li> <li><a href="/wiki/Malware" title="Malware">Malware</a> <ul><li><a href="/wiki/Infostealer" title="Infostealer">Infostealer</a></li> <li><a href="/wiki/Ransomware" title="Ransomware">Ransomware</a></li> <li><a href="/wiki/Spyware" title="Spyware">Spyware</a></li> <li><a href="/wiki/Trojan_horse_(computing)" title="Trojan horse (computing)">Trojan horse</a></li> <li><a href="/wiki/Computer_worm" title="Computer worm">Worm</a></li></ul></li> <li><a href="/wiki/Scareware" title="Scareware">Scareware</a></li> <li><a href="/wiki/Shovelware" title="Shovelware">Shovelware</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Software_release_life_cycle" title="Software release life cycle">Software release life cycle</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abandonware" title="Abandonware">Abandonware</a></li> <li><a href="/wiki/End-of-life_product" title="End-of-life product">End-of-life</a></li> <li><a href="/wiki/Long-term_support" title="Long-term support">Long-term support</a></li> <li><a href="/wiki/Software_maintenance" title="Software maintenance">Software maintenance</a></li> <li><a href="/wiki/Software_maintainer" title="Software maintainer">Software maintainer</a></li> <li><a href="/wiki/Software_publisher" title="Software publisher">Software publisher</a></li> <li><a href="/wiki/Vaporware" title="Vaporware">Vaporware</a> <ul><li><a href="/wiki/List_of_vaporware" title="List of vaporware">list</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Copy_protection" title="Copy protection">Copy protection</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Digital_rights_management" title="Digital rights management">Digital rights management</a></li> <li><a href="/wiki/Software_protection_dongle" title="Software protection dongle">Software protection dongle</a></li> <li><a href="/wiki/License_manager" class="mw-redirect" title="License manager">License manager</a></li> <li><a href="/wiki/Product_activation" title="Product activation">Product activation</a></li> <li><a href="/wiki/Product_key" title="Product key">Product key</a></li> <li><a href="/wiki/Software_copyright" title="Software copyright">Software copyright</a></li> <li><a href="/wiki/Software_license_server" title="Software license server">Software license server</a></li> <li><a href="/wiki/Software_patent" title="Software patent">Software patent</a></li> <li><a href="/wiki/Torrent_poisoning" title="Torrent poisoning">Torrent poisoning</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Free_and_open-source_software510" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:FOSS" title="Template:FOSS"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:FOSS" title="Template talk:FOSS"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:FOSS" title="Special:EditPage/Template:FOSS"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Free_and_open-source_software510" style="font-size:114%;margin:0 4em"><a href="/wiki/Free_and_open-source_software" title="Free and open-source software">Free and open-source software</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">General</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alternative_terms_for_free_software" title="Alternative terms for free software">Alternative terms for free software</a></li> <li><a href="/wiki/Comparison_of_open-source_and_closed-source_software" title="Comparison of open-source and closed-source software">Comparison of open-source and closed-source software</a></li> <li><a href="/wiki/Comparison_of_source-code-hosting_facilities" title="Comparison of source-code-hosting facilities">Comparison of source-code-hosting facilities</a></li> <li><a href="/wiki/Free_software" title="Free software">Free software</a></li> <li><a href="/wiki/List_of_free_software_project_directories" title="List of free software project directories">Free software project directories</a></li> <li><a href="/wiki/Gratis_versus_libre" title="Gratis versus libre">Gratis versus libre</a></li> <li><a href="/wiki/Long-term_support" title="Long-term support">Long-term support</a></li> <li><a href="/wiki/Open-source_software" title="Open-source software">Open-source software</a></li> <li><a href="/wiki/Open-source_software_development" title="Open-source software development">Open-source software development</a></li> <li><a href="/wiki/Outline_of_free_software" title="Outline of free software">Outline</a></li> <li><a href="/wiki/Timeline_of_free_and_open-source_software" title="Timeline of free and open-source software">Timeline</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_free_and_open-source_software_packages" title="List of free and open-source software packages">Software<br />packages</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Comparison_of_free_software_for_audio" title="Comparison of free software for audio">Audio</a></li> <li><a href="/wiki/List_of_open-source_bioinformatics_software" title="List of open-source bioinformatics software">Bioinformatics</a></li> <li><a href="/wiki/List_of_open-source_codecs" title="List of open-source codecs">Codecs</a></li> <li><a href="/wiki/Comparison_of_open-source_configuration_management_software" title="Comparison of open-source configuration management software">Configuration management</a></li> <li><a href="/wiki/Device_driver" title="Device driver">Drivers</a> <ul><li><a href="/wiki/Free_and_open-source_graphics_device_driver" title="Free and open-source graphics device driver">Graphics</a></li> <li><a href="/wiki/Comparison_of_open-source_wireless_drivers" title="Comparison of open-source wireless drivers">Wireless</a></li></ul></li> <li><a href="/wiki/List_of_open-source_health_software" title="List of open-source health software">Health</a></li> <li><a href="/wiki/List_of_open-source_software_for_mathematics" title="List of open-source software for mathematics">Mathematics</a></li> <li><a href="/wiki/List_of_office_suites" title="List of office suites">Office suites</a></li> <li><a href="/wiki/Comparison_of_open-source_operating_systems" title="Comparison of open-source operating systems">Operating systems</a></li> <li><a href="/wiki/List_of_open-source_routing_platforms" title="List of open-source routing platforms">Routing</a></li> <li><a href="/wiki/List_of_free_television_software" title="List of free television software">Television</a></li> <li><a href="/wiki/List_of_open-source_video_games" title="List of open-source video games">Video games</a></li> <li><a href="/wiki/List_of_free_and_open-source_web_applications" title="List of free and open-source web applications">Web applications</a> <ul><li><a href="/wiki/Comparison_of_shopping_cart_software" title="Comparison of shopping cart software">E-commerce</a></li></ul></li> <li><a href="/wiki/List_of_free_and_open-source_Android_applications" title="List of free and open-source Android applications">Android apps</a></li> <li><a href="/wiki/List_of_free_and_open-source_iOS_applications" title="List of free and open-source iOS applications">iOS apps</a></li> <li><a href="/wiki/List_of_commercial_open-source_applications_and_services" title="List of commercial open-source applications and services">Commercial</a></li> <li><a href="/wiki/List_of_formerly_proprietary_software" title="List of formerly proprietary software">Formerly proprietary</a></li> <li><a href="/wiki/List_of_formerly_free_and_open-source_software" class="mw-redirect" title="List of formerly free and open-source software">Formerly open-source</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Community_of_practice" title="Community of practice">Community</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Free_software_movement" title="Free software movement">Free software movement</a></li> <li><a href="/wiki/History_of_free_and_open-source_software" title="History of free and open-source software">History</a></li> <li><a href="/wiki/Open-source-software_movement" class="mw-redirect" title="Open-source-software movement">Open-source-software movement</a></li> <li><a href="/wiki/List_of_free-software_events" title="List of free-software events">Events</a></li> <li><a href="/wiki/Open-source_software_advocacy" title="Open-source software advocacy">Advocacy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_free_and_open-source_software_organizations" title="List of free and open-source software organizations">Organisations</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Free_Software_Movement_of_India" title="Free Software Movement of India">Free Software Movement of India</a></li> <li><a href="/wiki/Free_Software_Foundation" title="Free Software Foundation">Free Software Foundation</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Free-software_license" title="Free-software license">Licenses</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Academic_Free_License" title="Academic Free License">AFL</a></li> <li><a href="/wiki/Apache_License" title="Apache License">Apache</a></li> <li><a href="/wiki/Apple_Public_Source_License" title="Apple Public Source License">APSL</a></li> <li><a href="/wiki/Artistic_License" title="Artistic License">Artistic</a></li> <li><a href="/wiki/Beerware" title="Beerware">Beerware</a></li> <li><a href="/wiki/BSD_licenses" title="BSD licenses">BSD</a></li> <li><a href="/wiki/Creative_Commons_license" title="Creative Commons license">Creative Commons</a></li> <li><a href="/wiki/Common_Development_and_Distribution_License" title="Common Development and Distribution License">CDDL</a></li> <li><a href="/wiki/Eclipse_Public_License" title="Eclipse Public License">EPL</a></li> <li><a href="/wiki/Free_Software_Foundation" title="Free Software Foundation">Free Software Foundation</a> <ul><li><a href="/wiki/GNU_General_Public_License" title="GNU General Public License">GNU GPL</a></li> <li><a href="/wiki/GNU_Affero_General_Public_License" title="GNU Affero General Public License">GNU AGPL</a></li> <li><a href="/wiki/GNU_Lesser_General_Public_License" title="GNU Lesser General Public License">GNU LGPL</a></li></ul></li> <li><a href="/wiki/ISC_license" title="ISC license">ISC</a></li> <li><a href="/wiki/MIT_License" title="MIT License">MIT</a></li> <li><a href="/wiki/Mozilla_Public_License" title="Mozilla Public License">MPL</a></li> <li><a href="/wiki/Python_License" title="Python License">Python</a></li> <li><a href="/wiki/Python_Software_Foundation_License" title="Python Software Foundation License">Python Software Foundation License</a></li> <li><a href="/wiki/Shared_Source_Initiative" title="Shared Source Initiative">Shared Source Initiative</a></li> <li><a href="/wiki/Sleepycat_License" class="mw-redirect" title="Sleepycat License">Sleepycat</a></li> <li><a href="/wiki/Unlicense" title="Unlicense">Unlicense</a></li> <li><a href="/wiki/WTFPL" title="WTFPL">WTFPL</a></li> <li><a href="/wiki/Zlib_License" title="Zlib License">zlib</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Types_and_standards23" scope="row" class="navbox-group" style="width:1%">Types and<br /> standards</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Comparison_of_free_and_open-source_software_licenses" title="Comparison of free and open-source software licenses">Comparison of licenses</a></li> <li><a href="/wiki/Contributor_License_Agreement" title="Contributor License Agreement">Contributor License Agreement</a></li> <li><a href="/wiki/Copyleft" title="Copyleft">Copyleft</a></li> <li><a href="/wiki/Debian_Free_Software_Guidelines" class="mw-redirect" title="Debian Free Software Guidelines">Debian Free Software Guidelines</a></li> <li><a href="/wiki/Definition_of_Free_Cultural_Works" title="Definition of Free Cultural Works">Definition of Free Cultural Works</a></li> <li><a href="/wiki/Free_license" title="Free license">Free license</a></li> <li><a href="/wiki/The_Free_Software_Definition" title="The Free Software Definition">The Free Software Definition</a></li> <li><a href="/wiki/The_Open_Source_Definition" title="The Open Source Definition">The Open Source Definition</a></li> <li><a class="mw-selflink selflink">Open-source license</a></li> <li><a href="/wiki/Permissive_software_license" title="Permissive software license">Permissive software license</a></li> <li><a href="/wiki/Public_domain" title="Public domain">Public domain</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Challenges</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Digital_rights_management" title="Digital rights management">Digital rights management</a></li> <li><a href="/wiki/License_proliferation" title="License proliferation">License proliferation</a></li> <li><a href="/wiki/Mozilla_software_rebranded_by_Debian" class="mw-redirect" title="Mozilla software rebranded by Debian">Mozilla software rebranding</a></li> <li><a href="/wiki/Proprietary_device_driver" class="mw-redirect" title="Proprietary device driver">Proprietary device drivers</a></li> <li><a href="/wiki/Proprietary_firmware" title="Proprietary firmware">Proprietary firmware</a></li> <li><a href="/wiki/Proprietary_software" title="Proprietary software">Proprietary software</a></li> <li><a href="/wiki/SCO%E2%80%93Linux_disputes" title="SCO–Linux disputes">SCO/Linux controversies</a></li> <li><a href="/wiki/Software_patents_and_free_software" title="Software patents and free software">Software patents</a></li> <li><a href="/wiki/Open-source_software_security" title="Open-source software security">Software security</a></li> <li><a href="/wiki/Tivoization" title="Tivoization">Tivoization</a></li> <li><a href="/wiki/Trusted_Computing" title="Trusted Computing">Trusted Computing</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related <br />topics</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fork_(software_development)" title="Fork (software development)">Forking</a></li> <li><i><a href="/wiki/GNU_Manifesto" title="GNU Manifesto">GNU Manifesto</a></i></li> <li><a href="/wiki/Microsoft_Open_Specification_Promise" title="Microsoft Open Specification Promise">Microsoft Open Specification Promise</a></li> <li><a href="/wiki/Open-core_model" title="Open-core model">Open-core model</a></li> <li><a href="/wiki/Open-source_hardware" title="Open-source hardware">Open-source hardware</a></li> <li><a href="/wiki/Shared_Source_Initiative" title="Shared Source Initiative">Shared Source Initiative</a></li> <li><a href="/wiki/Source-available_software" title="Source-available software">Source-available software</a></li> <li><i><a href="/wiki/The_Cathedral_and_the_Bazaar" title="The Cathedral and the Bazaar">The Cathedral and the Bazaar</a></i></li> <li><i><a href="/wiki/Revolution_OS" title="Revolution OS">Revolution OS</a></i></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="font-weight:bold"><div> <ul><li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Symbol_portal_class.svg" class="mw-file-description" title="Portal"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/16px-Symbol_portal_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/23px-Symbol_portal_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/31px-Symbol_portal_class.svg.png 2x" data-file-width="180" data-file-height="185" /></a></span> <a href="/wiki/Portal:Free_and_open-source_software" title="Portal:Free and open-source software">Portal</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Free_software" title="Category:Free software">Category</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Open-source_license&oldid=1277721558">https://en.wikipedia.org/w/index.php?title=Open-source_license&oldid=1277721558</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Free_and_open-source_software_licenses" title="Category:Free and open-source software licenses">Free and open-source software licenses</a></li><li><a href="/wiki/Category:Terms_of_service" title="Category:Terms of service">Terms of service</a></li><li><a href="/wiki/Category:Free_culture_movement" title="Category:Free culture movement">Free culture movement</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Good_articles" title="Category:Good articles">Good articles</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Use_mdy_dates_from_January_2023" title="Category:Use mdy dates from January 2023">Use mdy dates from January 2023</a></li><li><a href="/wiki/Category:CS1:_long_volume_value" title="Category:CS1: long volume value">CS1: long volume value</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 26 February 2025, at 09:21<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Open-source_license&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><picture><source media="(min-width: 500px)" srcset="/static/images/footer/wikimedia-button.svg" width="84" height="29"><img src="/static/images/footer/wikimedia.svg" width="25" height="25" alt="Wikimedia Foundation" lang="en" loading="lazy"></picture></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><picture><source media="(min-width: 500px)" srcset="/w/resources/assets/poweredby_mediawiki.svg" width="88" height="31"><img src="/w/resources/assets/mediawiki_compact.svg" alt="Powered by MediaWiki" width="25" height="25" loading="lazy"></picture></a></li> </ul> </footer> </div> </div> </div> <div class="vector-header-container vector-sticky-header-container"> <div id="vector-sticky-header" class="vector-sticky-header"> <div class="vector-sticky-header-start"> <div class="vector-sticky-header-icon-start vector-button-flush-left vector-button-flush-right" aria-hidden="true"> <button class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-sticky-header-search-toggle" tabindex="-1" data-event-name="ui.vector-sticky-search-form.icon"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </button> </div> <div role="search" class="vector-search-box-vue vector-search-box-show-thumbnail vector-search-box"> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail"> <form action="/w/index.php" id="vector-sticky-search-form" class="cdx-search-input cdx-search-input--has-end-button"> <div class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia"> <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <div class="vector-sticky-header-context-bar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-sticky-header-toc" class="vector-dropdown mw-portlet mw-portlet-sticky-header-toc vector-sticky-header-toc vector-button-flush-left" > <input type="checkbox" id="vector-sticky-header-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-sticky-header-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-sticky-header-toc-label" for="vector-sticky-header-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-sticky-header-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div class="vector-sticky-header-context-bar-primary" aria-hidden="true" ><span class="mw-page-title-main">Open-source license</span></div> </div> </div> <div class="vector-sticky-header-end" aria-hidden="true"> <div class="vector-sticky-header-icons"> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-talk-sticky-header" tabindex="-1" data-event-name="talk-sticky-header"><span class="vector-icon mw-ui-icon-speechBubbles mw-ui-icon-wikimedia-speechBubbles"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-subject-sticky-header" tabindex="-1" data-event-name="subject-sticky-header"><span class="vector-icon mw-ui-icon-article mw-ui-icon-wikimedia-article"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-history-sticky-header" tabindex="-1" data-event-name="history-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-history mw-ui-icon-wikimedia-wikimedia-history"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only mw-watchlink" id="ca-watchstar-sticky-header" tabindex="-1" data-event-name="watch-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-star mw-ui-icon-wikimedia-wikimedia-star"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-edit-sticky-header" tabindex="-1" data-event-name="wikitext-edit-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-wikiText mw-ui-icon-wikimedia-wikimedia-wikiText"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-ve-edit-sticky-header" tabindex="-1" data-event-name="ve-edit-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-edit mw-ui-icon-wikimedia-wikimedia-edit"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-viewsource-sticky-header" tabindex="-1" data-event-name="ve-edit-protected-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-editLock mw-ui-icon-wikimedia-wikimedia-editLock"></span> <span></span> </a> </div> <div class="vector-sticky-header-buttons"> <button class="cdx-button cdx-button--weight-quiet mw-interlanguage-selector" id="p-lang-btn-sticky-header" tabindex="-1" data-event-name="ui.dropdown-p-lang-btn-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-language mw-ui-icon-wikimedia-wikimedia-language"></span> <span>15 languages</span> </button> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive" id="ca-addsection-sticky-header" tabindex="-1" data-event-name="addsection-sticky-header"><span class="vector-icon mw-ui-icon-speechBubbleAdd-progressive mw-ui-icon-wikimedia-speechBubbleAdd-progressive"></span> <span>Add topic</span> </a> </div> <div class="vector-sticky-header-icon-end"> <div class="vector-user-links"> </div> </div> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-6cc877bdc-wkvq8","wgBackendResponseTime":130,"wgPageParseReport":{"limitreport":{"cputime":"1.125","walltime":"1.295","ppvisitednodes":{"value":12178,"limit":1000000},"postexpandincludesize":{"value":143513,"limit":2097152},"templateargumentsize":{"value":17745,"limit":2097152},"expansiondepth":{"value":19,"limit":100},"expensivefunctioncount":{"value":13,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":172004,"limit":5000000},"entityaccesscount":{"value":0,"limit":400},"timingprofile":["100.00% 1107.625 1 -total"," 35.65% 394.814 145 Template:Sfn"," 18.06% 200.044 1 Template:Reflist"," 10.39% 115.063 3 Template:Navbox"," 8.69% 96.283 156 Template:Main_other"," 8.44% 93.433 1 Template:Software_licenses"," 8.03% 88.970 4 Template:Cite_web"," 6.45% 71.388 14 Template:Cite_journal"," 6.43% 71.215 1 Template:Short_description"," 6.38% 70.703 4 Template:Cite_court"]},"scribunto":{"limitreport-timeusage":{"value":"0.680","limit":"10.000"},"limitreport-memusage":{"value":8076125,"limit":52428800},"limitreport-logs":"anchor_id_list = table#1 {\n [\"CITEREFBainSmith2022\"] = 1,\n [\"CITEREFBallhausen2019\"] = 1,\n [\"CITEREFBallhausen2022\"] = 1,\n [\"CITEREFBernelin2020\"] = 1,\n [\"CITEREFBrock2022\"] = 1,\n [\"CITEREFByfield2008\"] = 1,\n [\"CITEREFCarver2005\"] = 1,\n [\"CITEREFChestek2022\"] = 1,\n [\"CITEREFColeman2004\"] = 1,\n [\"CITEREFDiBonaStoneOckman1999\"] = 1,\n [\"CITEREFFagundesPerzanowski2020\"] = 1,\n [\"CITEREFFontana2010\"] = 1,\n [\"CITEREFGreenbaum2016\"] = 1,\n [\"CITEREFHammerlyPaquinWalton1999\"] = 1,\n [\"CITEREFJoy2022\"] = 1,\n [\"CITEREFKeats2010\"] = 1,\n [\"CITEREFKunert2022\"] = 1,\n [\"CITEREFMaracke2019\"] = 1,\n [\"CITEREFMeeker2020\"] = 1,\n [\"CITEREFOSI2023\"] = 1,\n [\"CITEREFOman2018\"] = 1,\n [\"CITEREFOmbredanne2020\"] = 1,\n [\"CITEREFOnettiVerma2009\"] = 1,\n [\"CITEREFPerens1999\"] = 1,\n [\"CITEREFRaymond1999\"] = 1,\n [\"CITEREFRaymond2001\"] = 1,\n [\"CITEREFRosen2005\"] = 1,\n [\"CITEREFRoss2021\"] = 1,\n [\"CITEREFSenSubramaniamNelson2008\"] = 1,\n [\"CITEREFSmith2019\"] = 1,\n [\"CITEREFSmith2022\"] = 1,\n [\"CITEREFSt._Laurent2004\"] = 1,\n [\"CITEREFTsai2008\"] = 1,\n [\"CITEREFWakabayashi2019\"] = 1,\n [\"CITEREFWalden2022\"] = 1,\n [\"CITEREFWilliams2002\"] = 1,\n}\ntemplate_list = table#1 {\n [\"Category\"] = 3,\n [\"Cite AV media\"] = 1,\n [\"Cite book\"] = 8,\n [\"Cite court\"] = 4,\n [\"Cite journal\"] = 14,\n [\"Cite news\"] = 2,\n [\"Cite web\"] = 4,\n [\"Cmn\"] = 1,\n [\"FOSS\"] = 1,\n [\"Good article\"] = 1,\n [\"Harvc\"] = 8,\n [\"Harvnb\"] = 2,\n [\"Main\"] = 6,\n [\"Refbegin\"] = 1,\n [\"Refend\"] = 1,\n [\"Reflist\"] = 1,\n [\"See also\"] = 1,\n [\"Sfn\"] = 145,\n [\"Short description\"] = 1,\n [\"Software licenses\"] = 1,\n [\"Use mdy dates\"] = 1,\n}\narticle_whitelist = table#1 {\n}\nciteref_patterns = table#1 {\n}\n"},"cachereport":{"origin":"mw-api-ext.codfw.main-c4cdbd856-kqqwt","timestamp":"20250226092155","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Open-source license","url":"https:\/\/en.wikipedia.org\/wiki\/Open-source_license","sameAs":"http:\/\/www.wikidata.org\/entity\/Q97044024","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q97044024","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2001-05-14T17:50:17Z","dateModified":"2025-02-26T09:21:54Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/8\/86\/Open-source-license-chart.svg","headline":"license for computer software and other products that allows the source code, blueprint or design to be used, modified and\/or shared under defined terms and conditions"}</script> </body> </html>