[O]n his classical/rock fusion album Classical Graffiti (played by octet the Planets), he included a self-explanatory track called A One Minute Silence. Credited to Batt/Cage, it seemed a deliberate but innocuous echo of 4'33"[.]
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Classical Graffiti soared to the top of the classical charts, where it remained for a lucrative three months. Eight weeks into this reign, however, Cage's publishers, Peters Edition, contacted Batt and declared that he had, as it were, no right to silence.
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For example, Frank Zappa made a recording of 4'33" that was credited to John Cage, and for which royalties were paid. Indeed, for him the case was less about the highbrow question of whether or not silence can be copyright, but about whether or not this was actually a performace of Cage's piece. Having seen "Cage" on the sleeve (and "John Cage" on relevant documentation), says Riddle, "from our point of view they had established that they intended this to be a performance of - or at least a quotation from! - 4'33", not just borrowing Cage's creative idea, which it is difficult to regard as copyright under British law, but actually purporting to have recorded that work."