Alzrius
The EN World kitten
That 3 year statute of limitations would apply to damages of a particular violation not to the copyright itself. The copyright itself is valid for life of the author+75 years or 95 years for corporate owned copyrights.
This is a minor nitpick, but unless it's changed in the last few months, it's the life of the author plus seventy years, or 95 years for corporate works - that only universally applies to works published in the US after 2002, of course.
For a complete breakdown of what works enter the public domain when, see the following handy guide: http://www.copyright.cornell.edu/public_domain/