From The Statute of Anne To Z.Z. Top: The Strange World of American Sound Recordings, How it Came About, And Why it Will Never Go Away, 15 J. Marshall Rev. Intell. Prop. L. 1 (2015)

Uniquely among all industrialized nations, the United States extended no copyright protection to sound recordings until 1972. The individual aural representation captured for playback could only be protected by the common or statutory laws of individual states. This feature was carried forward into the comprehensive revision of the Copyright Act implemented on January 1, 1978. Although the Copyright Act contained a sweeping provision that brought works created prior to the legislation under federal protection, pre-1972 sound recordings were specifically exempted.

The extent to which this lack of status has created a legal and environmental void is best demonstrated by a series of cases litigated in New York from 2003 to 2006, known colloquially as the Capitol v. Naxos cases. They involved a series of classical music recordings made in England in the 1930s and reissued in 1999, over a decade after their United Kingdom copyright had expired. The critical New York state court case—Capitol v. Naxos IV—strongly implied that states have a fundamental power of copyright covering those things defined in the Constitution as writings, but which do not fall under federal copyright. Moreover, federal copyright does not extinguish such state powers, but instead merely preempts them for the duration of federal protection, at which point state copyright reverts—in perpetuity.