>May a voice from the back of the hall
>ask why LaTeX doesn't adopt the Gnu GPL?
I feel sure the experts here can give much better answer:
But the objective of the GNU license is to make sure that the sources and
the derivations as far as possible stay open and free, but they are freely
By contrast, LaTeX, in addition wants to make sure that the various LaTeX
installations will behave the same when compiling the same input, or if
that is not the case, that the user is clearly made aware about that.
BTW. MacOS pre-X used to have "creator codes" identifying programs
independent of their file name.
A LaTeX version might be to attach a "creator" name to each file, which
must be altered to a unique one if the original file is modified and should
be distributed. For example, the original files might have creator "LaTeX
Project Core" etc.
Apple keeps a database of these creator codes, where one can register them
in order to make sure that they do not clash. This only necessary if one
think there is a risk for clash.
The LPPL would then say that if some sources have a LaTeX creator code,
then if those sources are altered, also the creator code must be altered.
The advantage of this approach is that the identity of the sources is not
entirely tied to the file name.