Under U.S. law, music published before 1923 is in public domain. Newer editions of public domain works may be under copyright. Before 1976, U.S. Copyright Law provided, for registered works, copyright for 28 years, renewable for an additional 28 years. Revisions to the law in 1976 provided the term of copyright as the original 28 years plus an additional 47 years (totaling 75 years). Newer revisions added 20 years to the term of copyright (totaling 95 years).
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