en/setup/start/licenses.html - platform/docs/source.android.com - Git at Google

 <html devsite>
   <head>
     <title>Content License</title>
     <meta name="project_path" value="/_project.yaml" />
     <meta name="book_path" value="/_book.yaml" />
   </head>
   <body>
   <!--
       Copyright 2017 The Android Open Source Project

       Licensed under the Apache License, Version 2.0 (the "License");
       you may not use this file except in compliance with the License.
       You may obtain a copy of the License at

           http://www.apache.org/licenses/LICENSE-2.0

       Unless required by applicable law or agreed to in writing, software
       distributed under the License is distributed on an "AS IS" BASIS,
       WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
       See the License for the specific language governing permissions and
       limitations under the License.
   -->

 <p>
   The Android Open Source Project (AOSP) uses a few
   <a href="http://www.opensource.org/" class="external">open source
   initiative</a> approved open source licenses for our software.
 </p>
 <h2 id="android-open-source-project-license">AOSP license</h2>
 <p>
   The preferred license for AOSP is the
   <a href="http://www.apache.org/licenses/LICENSE-2.0" class="external">Apache
   Software License, Version 2.0</a> ("Apache 2.0"), and the majority of the
   Android software is licensed with Apache 2.0. While the project strives to
   adhere to the preferred license, there may be exceptions that will be handled
   on a case-by-case basis. For example, the Linux kernel patches are under the
   GPLv2 license with system exceptions, which can be found on
   <a href="http://www.kernel.org/pub/linux/kernel/COPYING" class="external">kernel.org</a>.
 </p>
 <h2 id="contributor-license-grants">Contributor License Agreements</h2>
 <p>All <em>individual</em> contributors (those making contributions only on
   their own behalf) of ideas, code, or documentation to AOSP will be required to
   complete, sign, and submit an
   <a href="https://cla.developers.google.com/about/google-individual" class="external">Individual
   Contributor License Agreement</a>. The agreement can be executed online
   through the
   <a href="https://android-review.googlesource.com/#/settings/agreements" class="external">code
   review tool</a>. The agreement clearly defines the terms under which
   intellectual property has been contributed to AOSP. This license is for your
   protection as a contributor as well as the protection of the project; it does
   not change your rights to use your own contributions for any other purpose.
 </p>
 <p>
   For a <em>corporation</em> (or other entity) that has assigned employees to
   work on AOSP, a
   <a href="https://cla.developers.google.com/about/google-corporate" class="external">Corporate
   Contributor License Agreement</a> is available. This version of the agreement
   allows a corporation to authorize contributions submitted by its designated
   employees and to grant copyright and patent licenses. A Corporate Contributor
   License Agreement does not remove the need for any developer to sign their own
   Individual Contributor License Agreement as an individual. The individual
   agreement is needed to cover any of their contributions that are <em>not</em>
   owned by the corporation signing the Corporate Contributor License Agreement.
 </p>
 <p>
   We based our agreements on the ones used by the
   <a href="http://www.apache.org">Apache Software Foundation</a>, which can
   be found on the
   <a href="http://www.apache.org/licenses/" class="external">Apache website</a>.
 </p>
 <h2 id="why-apache-software-license">Why Apache Software License?</h2>
 <p>
   We are sometimes asked why Apache Software License 2.0 is the preferred
   license for Android. For userspace (non-kernel) software, we prefer ASL2.0
   (and similar licenses such as BSD, MIT, etc.) over other licenses such as
   LGPL.
 </p>
 <p>
   Android is about freedom and choice. The purpose of Android is to promote
   openness in the mobile world, and we don't believe it's possible to predict or
   dictate all the uses to which people will want to put our software. So, while
   we encourage everyone to make devices that are open and modifiable, we don't
   believe it is our place to force them to do so. Using LGPL libraries would
   often force them to do just that.
 </p>
 <p>
   Here are some of our specific concerns:
 </p>
 <ul>
   <li>
     LGPL (in simplified terms) requires either: shipping of source to the
     application; a written offer for source; or linking the LGPL-ed library
     dynamically and allowing users to manually upgrade or replace the library.
     Since Android software is typically shipped in the form of a static system
     image, complying with these requirements restricts OEMs' designs. For
     instance, it's difficult for a user to replace a library on read-only
     flash storage.)
   </li>
   <li>
     LGPL requires allowance of customer modification and reverse
     engineering for debugging those modifications. Most device makers do
     not want to have to be bound by these terms. So to minimize the burden on
     these companies, we minimize usage of LGPL software in userspace.
   </li>
   </li>
   <li>
     Historically, LGPL libraries have been the source of a large number
     of compliance problems for downstream device makers and application
     developers. Educating engineers on these issues is difficult and slow-going,
     unfortunately. It's critical to Android's success that it be as easy as
     possible for device makers to comply with the licenses. Given the
     difficulties with complying with LGPL in the past, it is most prudent to
     simply not use LGPL libraries if we can avoid it.
   </li>
 </ul>
 <p>
   The issues discussed above are our reasons for preferring ASL2.0 for
   our own code. They aren't criticisms of LGPL or other licenses. We are
   passionate about this topic, even to the point where we've gone out of our
   way to make sure as much code as possible is ASL2.0 licensed. However, we love
   all free and open source licenses, and respect others' opinions and
   preferences. We've simply decided ASL2.0 is the right license for our goals.
 </p>

   </body>
 </html>
	<html devsite>
	<head>
	<title>Content License</title>
	<meta name="project_path" value="/_project.yaml" />
	<meta name="book_path" value="/_book.yaml" />
	</head>
	<body>
	<!--
	Copyright 2017 The Android Open Source Project

	Licensed under the Apache License, Version 2.0 (the "License");
	you may not use this file except in compliance with the License.
	You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	-->

	<p>
	The Android Open Source Project (AOSP) uses a few
	<a href="http://www.opensource.org/" class="external">open source
	initiative</a> approved open source licenses for our software.
	</p>
	<h2 id="android-open-source-project-license">AOSP license</h2>
	<p>
	The preferred license for AOSP is the
	<a href="http://www.apache.org/licenses/LICENSE-2.0" class="external">Apache
	Software License, Version 2.0</a> ("Apache 2.0"), and the majority of the
	Android software is licensed with Apache 2.0. While the project strives to
	adhere to the preferred license, there may be exceptions that will be handled
	on a case-by-case basis. For example, the Linux kernel patches are under the
	GPLv2 license with system exceptions, which can be found on
	<a href="http://www.kernel.org/pub/linux/kernel/COPYING" class="external">kernel.org</a>.
	</p>
	<h2 id="contributor-license-grants">Contributor License Agreements</h2>
	<p>All <em>individual</em> contributors (those making contributions only on
	their own behalf) of ideas, code, or documentation to AOSP will be required to
	complete, sign, and submit an
	<a href="https://cla.developers.google.com/about/google-individual" class="external">Individual
	Contributor License Agreement</a>. The agreement can be executed online
	through the
	<a href="https://android-review.googlesource.com/#/settings/agreements" class="external">code
	review tool</a>. The agreement clearly defines the terms under which
	intellectual property has been contributed to AOSP. This license is for your
	protection as a contributor as well as the protection of the project; it does
	not change your rights to use your own contributions for any other purpose.
	</p>
	<p>
	For a <em>corporation</em> (or other entity) that has assigned employees to
	work on AOSP, a
	<a href="https://cla.developers.google.com/about/google-corporate" class="external">Corporate
	Contributor License Agreement</a> is available. This version of the agreement
	allows a corporation to authorize contributions submitted by its designated
	employees and to grant copyright and patent licenses. A Corporate Contributor
	License Agreement does not remove the need for any developer to sign their own
	Individual Contributor License Agreement as an individual. The individual
	agreement is needed to cover any of their contributions that are <em>not</em>
	owned by the corporation signing the Corporate Contributor License Agreement.
	</p>
	<p>
	We based our agreements on the ones used by the
	<a href="http://www.apache.org">Apache Software Foundation</a>, which can
	be found on the
	<a href="http://www.apache.org/licenses/" class="external">Apache website</a>.
	</p>
	<h2 id="why-apache-software-license">Why Apache Software License?</h2>
	<p>
	We are sometimes asked why Apache Software License 2.0 is the preferred
	license for Android. For userspace (non-kernel) software, we prefer ASL2.0
	(and similar licenses such as BSD, MIT, etc.) over other licenses such as
	LGPL.
	</p>
	<p>
	Android is about freedom and choice. The purpose of Android is to promote
	openness in the mobile world, and we don't believe it's possible to predict or
	dictate all the uses to which people will want to put our software. So, while
	we encourage everyone to make devices that are open and modifiable, we don't
	believe it is our place to force them to do so. Using LGPL libraries would
	often force them to do just that.
	</p>
	<p>
	Here are some of our specific concerns:
	</p>
	<ul>
	<li>
	LGPL (in simplified terms) requires either: shipping of source to the
	application; a written offer for source; or linking the LGPL-ed library
	dynamically and allowing users to manually upgrade or replace the library.
	Since Android software is typically shipped in the form of a static system
	image, complying with these requirements restricts OEMs' designs. For
	instance, it's difficult for a user to replace a library on read-only
	flash storage.)
	</li>
	<li>
	LGPL requires allowance of customer modification and reverse
	engineering for debugging those modifications. Most device makers do
	not want to have to be bound by these terms. So to minimize the burden on
	these companies, we minimize usage of LGPL software in userspace.
	</li>
	</li>
	<li>
	Historically, LGPL libraries have been the source of a large number
	of compliance problems for downstream device makers and application
	developers. Educating engineers on these issues is difficult and slow-going,
	unfortunately. It's critical to Android's success that it be as easy as
	possible for device makers to comply with the licenses. Given the
	difficulties with complying with LGPL in the past, it is most prudent to
	simply not use LGPL libraries if we can avoid it.
	</li>
	</ul>
	<p>
	The issues discussed above are our reasons for preferring ASL2.0 for
	our own code. They aren't criticisms of LGPL or other licenses. We are
	passionate about this topic, even to the point where we've gone out of our
	way to make sure as much code as possible is ASL2.0 licensed. However, we love
	all free and open source licenses, and respect others' opinions and
	preferences. We've simply decided ASL2.0 is the right license for our goals.
	</p>

	</body>
	</html>