Think about this for a second. What I heard the judge saying is basically this (and something judges have repeatedly said): Copyright is not a barrier to comp

Think about this for a second. What I heard the judge saying is basically this (and something judges have repeatedly said): Copyright is not a barrier to competition with functionally equivalent products, nor is it a barrier to interoperability of functional software. WINE is not a derivative work of Windows, for example.... Instead copyright (at least in the US) only protects creative expression to the extent it can be separated from function. This means it protects source code in kind of funny ways and with strange boundaries which haven't been as fleshed out as much as one might think. This is important. It places a lot of the more extremist rhetoric about what the GPL prohibits in doubt too, since by this logic steps that are minimally necessary to interop with a piece of software can never, by themselves, rise to the level of copyright infringement.