For non-lawyers like me, have been reading around IP for interest and thought it might be useful to post some legal background resources:
WIPO, esp Berne Convention
Berne Convention - generally uses +50 years from date of death of auther
Universal Copyright Convention
The UCC generally only claims copyright for 25 years from date up publication or death of author. Clearly is has been overtaken by Berne in Berne signatory countries. Interesting to see that length of copyright has extended.
- note the specifics are copyright lasts +50 years from the end of the calendar year the author died
- mentions works copyright in countries covered by other conventions (Berne, UCC, Rome, WTO)
Arguments for extension of copyright beyond +50 years.
-life +20 to life +80
Project Gutenberg on copyright http://www.gutenberg.org/wiki/Gutenberg:Copyright_FAQ
Note that Project Gutenberg claims it is *only* beholden to US copyright law. I suspect that would be easily defeated if seriously challenged.
McGill University music copyright Q&A
Review of Napster Case - contains many points very relevant to IMSLP in respect of how one might argue NOT to be liable even when distributing material KNOWN to be infringing copyright, which IMSLP is not. (See especially the legal arguments section and the Betamax defense)