ciaran_o_riordan writes: "Tomorrow, a German court will hear the case of AVM, a distributor of Linux-based routers, which seeks to block Cybits from distributing software that modifies the routers' software to add content filtering functionality. FSFE explains: "AVM justified its position using three arguments. First, they stated that their whole product software must be regarded as an entity under AVM copyright, and that this entity must not be modified. The position Mr Welte took was that the whole product software would in that case be a derivative work according to the GPL, and thus the whole product software should be licensed under the GNU GPL. AVM then switched to a second argument: that the software embedded on its DSL terminals consisted of several parts. According to Mr Welte, AVM could then not prohibit anyone from modifying or distributing the GPL licensed software parts. The final argument by AVM was that the software on their DSL terminals is a composition of several different programs, which, due to the creative process, would be a protected compilation and thus under the copyright of AVM and not affected by the copyleft of the GPL.""