Michael J Fox's middle name is actually Andrew.

Michael’s first American role came in the 1979 made-for-TV movie Letters From Frank. For this film, he was credited using his given name: “Michael Fox.” Fox had planned on continuing to use this name until it came time for him to register with the Screen Actors Guild. The Guild does not allow for identical names to be entered more than once (to reduce confusion), and Fox found that a “Michael Fox” had already been registered. For this reason, he had to think of a new name for himself. He briefly considered going by his middle name but did not like the sound of “Andrew Fox” or “Andy Fox.” Therefore, he simply chose a new middle initial - “J” - an homage to actor Michael J. Pollard...this guy.
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