Musical plagiarism

Music plagiarism is the use or close imitation of another author's music while representing it as one's own original work. Plagiarism in music now occurs in two contexts—with a musical idea (that is, a melody or motif) or sampling (taking a portion of one sound recording and reusing it in a different song). For a legal history of the latter see sampling.

Any music that follows rules of a musical scale is limited by the ability to use a small number of notes. All forms of music can be said to include patterns. Algorithms (or, at the very least, formal sets of rules) have been used to compose music for centuries; the procedures used to plot voice-leading in Western counterpoint, for example, can often be reduced to algorithmic determinacy.

For these reasons, accidental or "unconscious" plagiarism is possible. As well, some artists abandon the stigma of plagiarism altogether. Composer Dmitri Shostakovich perhaps commented sarcastically on the issue of musical plagiarism with his use of "We Wish You a Merry Christmas," an instantly recognizable tune, in his Prelude No. 15 in D Flat, Op. 87. In some instances, it was also erroneously assumed that songs are still in copyright such as "Happy Birthday to You". In 2015, a lawsuit which challenged the copyright, found this was not the case.

Many songs are in public domain. For example, the work of Robert Johnson (1911 – 1938) is public domain in the European Union because Johnson died more than 70 years ago (1938 + 70). Some songs from W.C. Handy (1873 – 1958) are public domain in the USA because they were published before 1922 (e.g. "Memphis Blues"), but they are normally not public domain in the European Union until 2028 (1958 + 70). But the "Rule of the shorter term" (i.e. where copyright law overlaps, the law with the shorter term is upheld) makes them public domain in the states of the European Union.

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