---
title: "Software License Policy"
sidenav: docs
---

= Software License Policy

== Philosophy

The FreeBSD Project aims to produce a complete, BSD-licensed operating system allowing consumers of the system to produce derivative products without constraint or further license obligations.
We invite and greatly appreciate the contribution of both changes and additions under the two-clause BSD license, and encourage the adoption of this license by other open source projects.
Use of the BSD license is key to encouraging the adoption of advanced operating system technology, and on many notable occasions has been pivotal to widespread use of new technology.

We accept however that compelling reasons exist to allow differently-licensed software to be included in the FreeBSD source tree.

We require any software under alternative licenses to be carefully isolated in the source tree so that it cannot contaminate BSD-only components.
Such cautious management encourages licensing clarity and facilitates the production of BSD-only derivative products.

Unless a special exception is made, no existing BSD-licensed components may be replaced with differently-licensed software.
We instead encourage FreeBSD and third party developers to seek the relicensing or reimplementation of critical components under the BSD license.
Such would ease their more integral adoption into the FreeBSD operating system.

== Policy

* The import of new software licensed under any licenses other than the BSD license and BSD-Like Licenses (as defined below) requires the prior approval of the FreeBSD Core Team. Requests for import must include:
** A list of features or bug fixes that the new version or patches contain, along with evidence that our users need those features. PRs or references to mailing list discussions are ideal forms of evidence.
** A list of FreeBSD branches that may be affected. Expansions of scope require a new request to and approval from the FreeBSD Core Team.

* The Apache License 2.0 is acceptable for use in some cases. The Core Team must approve the import of new Apache License licensed components or the change of license of existing components to the Apache License.
** This license is approved for the following components:
*** LLVM toolchain and (with LLVM Exceptions) runtime components.
*** Subversion and its dependencies

* The BSD+Patent License is acceptable for use in some cases. The Core Team must approve the import of new BSD+Patent License licensed components or the change of license of existing components to the BSD+Patent License.
** This license is approved for the following components:
*** EDK2 derived code related to UEFI functionality

* The Common Development and Distribution License (CDDL) is acceptable for use in some cases. The Core Team must approve the import of new CDDL licensed components or the change of license of existing components to the CDDL.
** This license is approved for the following components:
*** DTrace
*** ZFS filesystem including kernel support and userland utilities

* Historically, the phrase 'All Rights Reserved.' was included in all copyright notices. The BSD releases had it to comply with the Buenos Aires Convention of 1910 in the Americas. With the ratification of the Berne Convention in 2000, it became obsolete. As such, the FreeBSD project recommends that new code omit the phrase and encourages existing copyright holders to remove it. In 2018, the project updated its templates to remove it.

=== Acceptable licenses

The following licenses are considered to be acceptable BSD-Like Licenses for the purpose of this Policy. They must be reproduced verbatim on any new code. Deviations or the use of any other license must be approved by the FreeBSD Core Team:

* The 2 clause version of the BSD license

....
/*
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) [year] [your name]
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
....
* The 3 clause version of the BSD license

....
/*
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) [year] [your name]
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the author nor the names of its contributors may
 *    be used to endorse or promote products derived from this software
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
....
* The ISC License

....
/*
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) [year] [copyright holder]
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
....
* The MIT License

....
/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright (c) [year] [copyright holders]
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
....

* It is acceptable to use use only the SPDX-License-Identifier
** See https://spdx.github.io/spdx-spec/[Annex D of SPDX Standard] for definition of standard SPDX-License-Identifier expressions used, how to interpret them and where to find the license text(s) that are applicable.
