The Python Software Foundation (PSF) license has been approved by the Open Source Initiative (OSI). Python is now eligible to mark its products using the license with the OSI Certified Open Source Software mark. The license is specific to the 2.1.1 release of Python, an interpreted, interactive, object-oriented
programming language. Python was written by Guido Van Rossum in the early 1990s. Van Rossum is a member of the OSI board.
While there are many software licenses that allow access to source code, only a handful are deemed true Open Source software licenses by OSI, a group founded for the purpose of "managing and promoting the Open Source Definition for the good of the community." The OSI board meets periodically to discuss and approve submitted licenses.
Additionally, candidates for acceptance by OSI are posted to the license-discuss mailing list. The PSF license received only positive comments and was considered likely to be passed by the board. Helping the case was the fact that the PSF license was already approved by the Free Software Foundation as being compatible with the General Public License (GPL) championed by Richard M. Stallman.
The content of the license is as follows:
PSF LICENSE AGREEMENT
1. This LICENSE AGREEMENT is between the Python Software Foundation
("PSF"), and the Individual or Organization ("Licensee") accessing and
otherwise using Python 2.1.1 software in source or binary form and its
2. Subject to the terms and conditions of this License Agreement, PSF
hereby grants Licensee a nonexclusive, royalty-free, world-wide
license to reproduce, analyze, test, perform and/or display publicly,
prepare derivative works, distribute, and otherwise use Python 2.1.1
alone or in any derivative version, provided, however, that PSF's
License Agreement and PSF's notice of copyright, i.e., "Copyright (c)
2001 Python Software Foundation; All Rights Reserved" are retained in
Python 2.1.1 alone or in any derivative version prepared by Licensee.
3. In the event Licensee prepares a derivative work that is based on
or incorporates Python 2.1.1 or any part thereof, and wants to make
the derivative work available to others as provided herein, then
Licensee hereby agrees to include in any such work a brief summary of
the changes made to Python 2.1.1.
4. PSF is making Python 2.1.1 available to Licensee on an "AS IS"
basis. PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
IMPLIED. BY WAY OF EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND
DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON 2.1.1 WILL NOT
INFRINGE ANY THIRD PARTY RIGHTS.
5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
2.1.1 FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 2.1.1,
OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
6. This License Agreement will automatically terminate upon a material
breach of its terms and conditions.
7. Nothing in this License Agreement shall be deemed to create any
relationship of agency, partnership, or joint venture between PSF and
Licensee. This License Agreement does not grant permission to use PSF
trademarks or trade name in a trademark sense to endorse or promote
products or services of Licensee, or any third party.
8. By copying, installing or otherwise using Python 2.1.1, Licensee
agrees to be bound by the terms and conditions of this License