Legal Question in Intellectual Property in California

Re: How long must an author be dead, before his work is public domain.

Ever? Yes. The date depends on a number of factors, however. For more information, please retain an intellectual property attorney to assist you and/or see

http://www.copyright.gov/help/faq/faq-duration.html

http://www.copyright.gov/records/cohm.html

http://www.incorporatecalifornia.com/inprop.html

http://incorporatecalifornia.com/enlaw.html

Best of luck,

Re: How long must an author be dead, before his work is public domain.

Yours would be a major undertaking in an arena where a hot contest is likely. You are best advised to retain your own intellectual property attorney.