You can't complain about the posting quality, then double post, and ask a question that was answered in the post before yoursThis is the type of reply that I asked to not have.
On subject - how long do patents last?
Yes, 20 years seems to be a kinda standard, but it's irrelevant as we already know the Rubiks patent has expired long ago. The issue is with them claiming the look of the cube is their trademark (which they have a duty to defent for fear of weakening it). However, there is no hard rule that says they Do have the trademark of the image of the cube... that needs to be decided in court. However I can't see them going to court with any of the chinese companies... it's much easier to threaten small companies who can't do anything about it (re: individual shops).