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In the United States, any musical works published before 1922, in addition to those voluntarily placed in public domain, exist in the public domain. In most other countries, music generally enters the public domain in a period of fifty to seventy-five years after the composer's death. (Public domain rights must be verified for each individual country.) It is important to note the distinction between 'musical works' (sheet music and other compositions) and 'sound recordings' (audio files, CDs, records), as virtually all sound recordings will not fall into public domain until 2067, unless explicitly placed into the public domain by its creators, rights holders or made by an employee or officer of the United States government acting under their official duty. (The status of copyright on sound recordings in the United States from before such copyrights were nationalized 1972 is nebulous; the copyrights were prior to that were considered a state issue, and even if no state law provided for it, some courts established an extra-legal common law copyright, the exact nature of which has been inconsistently applied over the years.)

how old does a song have to be to become public domain