Python Software Foundation License

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Python Software Foundation License
SPDX identifierPSF-2.0
Debian FSG compatible Yes
FSF approved Yes [1]
OSI approved No [2]
GPL compatible Yes [1]
Copyleft No
Guido van Rossum Guido van Rossum.jpg
Guido van Rossum

The Python Software Foundation License (PSFL) is a BSD-style, permissive software license which is compatible with the GNU General Public License (GPL). [1] Its primary use is for distribution of the Python project software and its documentation. [3] Since the license is permissive, it allows proprietization of the derivations. The PSFL is listed as approved on both FSF's approved licenses list, [1] and OSI's approved licenses list.


This license is also known as "Python License 2.0.1" [4] .

In 2000, Python (specifically version 2.1) was briefly available under the Python License, which is incompatible with the GPL. The reason given for this incompatibility by Free Software Foundation was that "this Python license is governed by the laws of the 'State of Virginia', in the USA", which the GPL does not permit. [5]

Guido van Rossum, Python's creator, was awarded the 2001 Free Software Foundation Award for the Advancement of Free Software [6] for changing the license to fix this incompatibility.

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  1. 1 2 3 4 Stallman, Richard. "Various Licenses and Comments about Them, new Python license". Free Software Foundation. Archived from the original on December 27, 2021. Retrieved July 7, 2007.
  2. "License Search". Open Source Initiative. OSI Approved Licenses.
  3. "Terms and conditions for accessing or otherwise using Python". Python Software Foundation. Archived from the original on December 25, 2021. Retrieved December 29, 2021.
  4. "Various Licenses and Comments about Them". Free Software Foundation. Retrieved April 13, 2023.
    "Python License 2.0.1". Software Package Data Exchange. SPDX License List.
  5. Stallman, Richard. "Various Licenses and Comments about Them, old Python license". Free Software Foundation. Retrieved July 7, 2007.
  6. "2001 Free Software Awards". GNU Project - Free Software Foundation. Archived from the original on August 14, 2021. Retrieved July 7, 2007.