Help:When does music enter the public domain?
Copyright laws vary from country to country and the rules and exceptions can be convoluted. Because of this CPDL is not in a position to offer legal advice. A few general guidelines follow:
Under U.S. copyright law, it is safe to assume all music published before 1923 is now public domain (though any changes in new editions of these works may still be copyrighted). Facsimiles of original older or out-of-copyright scores and older publications are not copyrightable. Before 1976, US Copyright Law stated that copyright existed for registered works for 28 years and could be renewed for an additional 28 years, and an exhaustive search for the required renewal can sometimes establish that a post-1923 work has fallen into the public domain. After 1976, US Copyright Law states that for music published before 1976, the term of copyright is the original 28 years plus an additional 47 years (equals 75 years). The 1998 Millennium Copyright Act extended the length of copyright for another 20 years, and does not require that a copyright notice appear on the publication. In general, once a work has entered the public domain it cannot be copyrighted again.
In European Common Market and some other countries the general rule is that copyright protection exists until 70 years after the death of the last creator (either the composer or the lyricist).
People downloading scores from CPDL should familiarize themselves with their local copyright laws. For example, a score may be on CPDL because the work has passed into the public domain in the U.S., but may still be under copyright in other countries.
Because CPDL is based in the U.S.A., users posting scores to CPDL need to ensure that the score complies with U.S. copyright law in addition to the laws of their own country.
More information about copyright: