Apple Public Source License

Last updated

Apple Public Source License
Author Apple Inc.
Latest version2.0
PublishedAugust 6, 2003
SPDX identifierAPSL-1.0, APSL-1.1, APSL-1.2, APSL-2.0
Debian FSG compatible No [1]
FSF approved Yes (Version 2.0, not versions 1.0, 1.1 and 1.2) [2] [3]
OSI approved Yes
GPL compatible No [2]
Copyleft Partial [4]
Linking from code with a different licence Yes [4]

The Apple Public Source License (APSL) is the open-source and free software license under which Apple's Darwin operating system was released in 2000. A free and open-source software license was voluntarily adopted to further involve the community from which much of Darwin originated.


The first version of the Apple Public Source License was approved by the Open Source Initiative (OSI). [5] Version 2.0, released July 29, 2003, is also approved as a free software license by the Free Software Foundation (FSF) which finds it acceptable for developers to work on projects that are already covered by this license. However, the FSF recommends that developers should not release new projects under this license, because the partial copyleft is not compatible with the GNU General Public License and allows linking with files released entirely as proprietary software. [4] The license does require that if any derivatives of the original source are released externally, their source should be made available; the Free Software Foundation compares this requirement to a similar one in its own GNU Affero General Public License. [4]

Many software releases from Apple have now been relicensed under the more liberal Apache License, such as the Bonjour Zeroconf stack. However, most OS component source code remains under APSL.

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The GNU Affero General Public License is a free, copyleft license published by the Free Software Foundation in November 2007, and based on the GNU GPL version 3 and the Affero General Public License.

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<span class="mw-page-title-main">GNU General Public License</span> Series of free software licenses

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<span class="mw-page-title-main">GNU Free Documentation License</span> Copyleft license primarily for free software documentation

The GNU Free Documentation License is a copyleft license for free documentation, designed by the Free Software Foundation (FSF) for the GNU Project. It is similar to the GNU General Public License, giving readers the rights to copy, redistribute, and modify a work and requires all copies and derivatives to be available under the same license. Copies may also be sold commercially, but, if produced in larger quantities, the original document or source code must be made available to the work's recipient.

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  1. "Apple Public Source License (APSL)". The Big DFSG-compatible Licenses. Debian Project . Retrieved January 27, 2017.
  2. 1 2 "Apple Public Source License (APSL), version 2.x". Various Licenses and Comments about Them. Free Software Foundation. Archived from the original on July 16, 2009. Retrieved July 6, 2009.
  3. "Various Licenses and Comments about Them - GNU Project - Free Software Foundation". September 3, 1999. Retrieved May 13, 2022.
  4. 1 2 3 4 FSF website
  5. Raymond, Eric. "OSI clarifies the status of the APSL". Linux Weekly News. Retrieved February 14, 2013.