Not on Youtube though we have had to with some cast photos being stolen, doctored and re-posted recently, in that case a polite but firm message pointing out our ownership sorted it all out.
As for what we post on Youtube, it is all our own work or clips we have had permission to film and upload.
If one of our our cast members or close contacts wanted to re-upload one of our clips with attached info, I dont think we would get in a sweat, it is when people re-upload things, having altered them, removed our info off them, or claimed as their own that the real stress would come in.