Am Montag, 21. Januar 2013 schrieb Ludovic Courtès:
> Seems like it’s either GPLv2+ or GPLv2-only.  Is there a v2-only file?

Good question. There are 530 C files...

I will follow the debian analysis at
   http://packages.debian.org/changelogs/pool/main/n/netpbm-free/netpbm-
free_10.0-12.2/libnetpbm10.copyright
and write down my findings here for future reference.

There is

fiasco: no license information inside netpbm, but it is distributed on its 
own as gpl2+, see   
   https://github.com/megatherion/Fiasco/blob/master/README

mdatopbm: gpl2+

pamstretch: gpl2+

pbmpage, pbmtoppa: This appears to be gpl2 only. The C files state:
 * Copyright (c) 1998 Tim Norman.  See LICENSE for details
And LICENSE is GPLv2.

So I will stop here and push as gpl2.

Andreas