Protection from copyright infringement for works created after 1977 extends throughout the life of the author who created the original work, plus 50 years after the author’s death (see 17 U.S.C. § 302[a]). When an original work is joint-authored, the copyright expires 50 years after the death of the last surviving author. Copyright is considered personal property that may be transferred to the author’s heirs upon his or her death. For works created prior to 1977, the duration of ownership depends upon the law that was in effect at the time a work was created. In many cases, original works were protected for only 28 years and have long since passed into the public domain, unprotected by U. S. copyright law.