Joe;

Re: artwork copyright...

The owner of the piece more or less has permanent non-expiring copyright to the art. My band just shelled out a few hundred to the Met for a Restoration period art piece (artist dead for a couple centuries). Even modern works are a permanent copyright to the 'owner' of the piece... it's one reason so many artists (who can afford to) refuse to sell the original, but offer 'reproductions', lithographs or other copies.

Technically, this means that even things like pre-historic cave paintings would likely be protected under copyright unless annexed as 'cultural treasures'.

M