Originally Posted by
artee
But surely (don't call me Shirley) it not the job of the FAA/EASA to rule on the IP's provenance.
Can't speak for the EASA but for the FAA its not their job. Different agency, set of laws, and courts. There is nothing in the FARs that prevents you from "copying" an existing product or article and using it provided you obtain your own FAA approvals. However, if you do infringe on someone else's IP that would be a separate matter and you may be subject to other legal actions even though you received FAA approval for the item.