Extrusion 3D printers derive from the research of the RepRap project, by Bowyer of Bath University, it is GPL.<p>The MakerBot derives from this GPLed work - the first MakerBot parts were printed by a RepRap.<p>This is a RepRap tradition that a RepRap print the parts for new RepRaps, a ceremonial self replication.<p>So the MakerBot&#x27;s intellectual property is not wholly their own and in fact is derives from a GPL licensed work.<p>Is this a GPL violation or did MakerBot relicense the RepRap from Bath ?<p>Perhaps the MakerBot is a &#x27;clean room&#x27; redesign of the RepRap, but Pettis, MakerBot&#x27;s founder was involved from the beginning and built RepRaps and the the MakerBot designs evolution (and initial part printing) from the RepRap is well documented by Make magazine.<p>MakerBots not being GPL licensed seems like a GPL violation but IANAL.