Some magic dealers claim intellectual property rights to certain magic tricks that were invented many decades ago by long-dead magicians and sold to these dealers. In other areas of society, ownership issues are disputed and controversial (example: land ownership). Were there such controversial discussions on the issue raised here? If so, where? Or are there people here with critical views who could describe their views? Many thanks for any information/viewpoint. I am specifically concerned here with magic tricks that were invented a long time ago by magicians who have since died. One example is the fantastic magic trick invented by magician Werry (1925 - 2000), probably in the 1950s, in which a forced card is produced from a hat using a rope. It could be argued that the gentlemen agreement that apparently only the dealer who bought the trick is allowed to produce the trick for an unlimited period of time is not in the interests of all people, but primarily in the financial interests of those who enter into the gentlemen agreement.