LaTeX Project Public License

The LaTeX Project Public License ( LPPL often abbreviated ) is a software license, originally written for the LaTeX typesetting environment and is widespread in the environment. It is suitable for the licensing of 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 by the Open Source Initiative as a free license has been accepted.

Basic intention

The LPPL evolved from the originally designed by Donald Knuth for TeX license. While this allowed the re-use of the source code for any purpose, but a software thus created could only be called TeX, if it satisfies all the requirements of the original canonical system. Knuth wanted to make this demand a high degree of compatibility, especially that future developments of existing TeX documents in a hundred years, yet can handle without any changes to the output would result:

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

Peculiarities of licensing

Filename clause

The file name clause is the most unusual - and equally controversial - special feature of the LPPL: It calls for a modified file is not under the same file name as the original file may be distributed. The Debian Linux community was considering to remove because of this clause all LPPL software from their GNU / Linux distribution, since it is not compatible with the Debian Free Software Guidelines (DFSG ).

This controversy led after thorough discussion to a relaxation of this rule in version 1.3 of the LPPL. Since then, it is sufficient if there is a component of both the source code and at run time clear and unambiguous outputs as a modified version, although a change of the file name is still recommended. This calmed the concerns raised by the Debian community.

Maintainer

The LPPL allows the designation of a maintainer to enable the further development of the software, even if the copyright of the original owner has in mind is no longer interested. A maintainer can hand over his position to a successor; he is no longer achievable, however, the maintainer status can be claimed by a new person and taken after a three month opposition period.

The maintainer is not particularly tied to the filename clause described above.

Copyright

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