Here at ETH I can tell you that it hasn't happened yet and we've produced quite a number of videos, and I think it's similar at other institutions that after 2,000 videos you can expect, say 1 or 2 people complaining about their video maybe not even with regard to copyright infringement but that's really a very low percentage so the question is are we worrying about nothing in the end? so that would be the risk assessment, so if there is no problem there's nothing that we specifically have to do with regard to copyright as I'm saying, this is just a solution that is being discussed 