AVM, Cybits tussle over SurfSitter, GPL

Several (German) news sites (see here, here and here) report on a dispute between AVM Computersysteme Vertiebs GmbH and Cybits AG. AVM, it seems, has been trying to stop Cybits modifying AVM's Linux-based Fritzbox firmware (a DSL terminal). If this Kat has understood the dispute correctly, it appears that Cybits’s SurfSitter DSL filter software downloads AVM-produced Fritzbox software on to a user's computer, modifies the software and afterwards re-installs it on the AVM-produced Fritzbox. SurfSitter is a child protection software program.


What makes this dispute so interesting is that part of the AVM-produced and Cybits-modified software falls under the General Public License (GPL). AVM reportedly bases its claim on copyright, trade mark law as well as unfair competition law and appears to argue, inter alia, that it holds the copyright for the overall product (Gesamtwerk), which in AVM’s own view does not fall within the scope of the GPL.


This dispute dates back to 2010, when AVM had initially obtained an interim injunction to stop distribution of Cybits' software. This case has now moved forward to full trial with Harald Welte having joined Cybits' camp in the proceedings as “intervener” (Streihelfer). Harald Welte is behind gpl-violations.org and is, according to Heise.de’s report, also supported by the Free Software Foundation Europe. Welte, who owns the copyright in part of the Linux Kernel, which is included in AVM’s as well as Cybits products, argues that AVM’s effort to prevent third parties like Cybits from distributing modified firmware violates the GPL which allows any third party to modify, recompile, re-install and run modified versions of the respective GPL licensed program (copyleft).




A hearing in this case has now taken place at the Landgericht Berlin on 21 June 2011. For more information on this case, from the view point of the Free Software Foundation Europe, click here. To read Harald Welte’s blogpost summarising with information on this case, click here. Meanwhile, if any of our readers has a link to website that explains AVM's view of the case, can he or she please let the Kat know, so that the links are not too one-sided.


UPDATE: please click here to read AVM's comment on this case (in English). As always, many thanks to readers for their comments. Once the court has handed down a decision, the Kats will of course let you know.