LaTeX Project Public License

The LaTeX Project Public License (often abbreviated to LPPL ) is a software license that was originally written for the LaTeX typesetting program and is widely used in its environment. It is suitable for licensing free software , but dispenses with a copyleft clause and is incompatible with many other licenses such as the GNU General Public License . In 2010 the license was recognized as a free license by the Open Source Initiative .

Basic intention

The LPPL developed from the license originally designed by Donald Knuth for TeX . This allowed the further use of the source code for any purpose, but software created with it could only be called TeX if it met all the requirements of the original canonical system. With this requirement, Knuth wanted to ensure a high degree of compatibility , in particular that future developments of TeX will still be able to process existing documents in a hundred years without any changes to the output:

"LPPL attempts to preserve the fact that something like LaTeX is a language which is used for communication, that is if you write a LaTeX document you expect to be able to send it to me and to work at my end like it does at yours. "

- Frank Mittelbach , main author of the LPPL

Special features of the license

Filename clause

The filename clause is the most unusual - and at the same time most controversial - peculiarity of the LPPL: It requires that a modified file must not be distributed under the same file name as the original file. The Debian Linux community was considering removing all LPPL software from their GNU / Linux distribution because of this clause, as it was inconsistent with the Debian Free Software Guidelines (DFSG) .

After thorough discussion, this controversy led to a relaxation of this requirement in version 1.3 of the LPPL. Since then, it has been sufficient for a component to clearly identify itself as a modified version, both in the source code and at runtime , although a change in the file name is still recommended. This allayed the Debian community's legal concerns.

Maintainer

The LPPL allows the naming of a maintainer in order to enable the further development of the software even if the original owner of the copyright is no longer interested. A maintainer can hand over his position to a successor; However, if he is no longer available, the maintainer status can be claimed by a new person and taken over after a three-month objection period.

In particular, the maintainer is not bound by the filename clause described above.

copyright

The copyright for the LPPL lies with the LaTeX project team, which is why it may be copied and distributed, but not changed. Analogous to the file name clause, however, it can serve as the basis for a new license under a new name.

Web links

The LaTeX project public license (English) - Publication of the current and older versions of the license.
Frank Mittelbach: Reflections on the history of the LaTeX Project Public License (LPPL) - A software license for LaTeX and more . In: TUGboat . The Communications of the TeX Users Group. tape 32 , no. 1 , 2011, p. 83–94 (English, PDF file, 362.6 kB [accessed on March 29, 2019]).

Individual evidence

^ LaTeX Project Public License (LPPL). Open Source Initiative (OSI), accessed on February 4, 2011 (English).
↑ LaTeX3 News. Issue 5. LaTeX Project, January 28, 2011, accessed on February 4, 2011 (English): “We are happy to report that earlier this year the LaTeX Project Public License (LPPL) has been approved by the OSI as an open source license . "
↑ Frank Mittelbach: Most compatible license with LPPL? September 23, 2007, accessed on February 4, 2011 (posted in the newsgroup comp.text.tex).
↑ The relevant discussion took place in the period from 2002 to 2003 on the English-language mailing list debian-legal, where the new version of the LPPL was also announced: Branden Robinson: Blast from the Past: the LaTeX Project Public License, version 1.3. Mailing list debian-legal, July 6, 2004, accessed on February 4, 2011 (English, Message-id: <20040706230904.GG29333@redwald.deadbeast.net>, with further references for discussion): “It looks like Mr. Mittelbach and the rest of the LaTeX3 Project took almost all of advice. I feel good about that. "

[1] LaTeX Project Public License (LPPL). Open Source Initiative (OSI), accessed on February 4, 2011 (English).

[2] LaTeX3 News. Issue 5. LaTeX Project, January 28, 2011, accessed on February 4, 2011 (English): “We are happy to report that earlier this year the LaTeX Project Public License (LPPL) has been approved by the OSI as an open source license . "

[3] Frank Mittelbach: Most compatible license with LPPL? September 23, 2007, accessed on February 4, 2011 (posted in the newsgroup comp.text.tex).

[4] The relevant discussion took place in the period from 2002 to 2003 on the English-language mailing list debian-legal, where the new version of the LPPL was also announced: Branden Robinson: Blast from the Past: the LaTeX Project Public License, version 1.3. Mailing list debian-legal, July 6, 2004, accessed on February 4, 2011 (English, Message-id: <20040706230904.GG29333@redwald.deadbeast.net>, with further references for discussion): “It looks like Mr. Mittelbach and the rest of the LaTeX3 Project took almost all of advice. I feel good about that. "