Hi, Wade Peterson of Silicore (the Wishbone people) has just released a loong article called 'The creation of interoperable integrated circuits using clean room design practice', a large part of which is about the legal hazards of trying to create free or open designs in a proprietary world. In particular he's proposing a system called 'CLASS' (Configurable Logic Array Superstructure) which should give a clear separation between parts of a design controlled by copyright law (and so ok to put under free licenses) and parts controlled by patent law. I don't have the legal knowledge to follow all the implications of this, would be interested to hear what others think. I've put a copy on http://www.opencollector.org/hardlicense/CleanRoomDsnPrac.pdf (with Wade's permission). Cheers Graham PS apologies if this arrives twice - I've forgotten which mail account I'm subscribed from...