Keaton was born Michael Douglas on September 5, 1951. He grew up the youngest of seven in a Pittsburgh suburb. When he was trying to make a go at acting in the 1970s, there were two other competitors. There was Kirk Douglas’s son Michael Douglas and a talkshow host named Mike Douglas. A quick look in the phone book inspired his new last name, Keaton, which proved to serve the man well.

Keaton’s breakout role came in the 1979 CBS sitcom Working Stiffs. And he would cement his comedic standing in films such as Night Shift and Mr. Mom and achieve superstardom with Beetlejuice and Batman.

These days, Keaton is changing his name again. He wants to be known as Michael Keaton Douglas from now on, as recently reported by People magazine, a hybrid of his stage and real names. It’s safe to say that he is certainly well-established enough now to avoid confusion.

Julianne Moore

Julianne Moore also had to use a stage name when joining a union (in this case, Actors’ Equity, the union for stage actors) and wasn’t too happy about it. She was born Julie Anne Smith. She looked to other family members’ monikers for inspiration.

“My father’s middle name is Moore; my mother’s name is Anne. So I just slammed the Anne onto the Julie,” she explained to the New York Times in 2001. “That way I could use both of their names and not hurt anyone’s feelings. . . . But it’s horrible to change your name. I’d been Julie Smith my whole life, and I didn’t want to change it.”

Emma Stone

Emily Jean Stone also found herself in this same situation when she was 16 years old, as she explained to W Magazine. She first tried out the name Riley, but she kept forgetting to answer to it on set. She finally landed on Emma because it sounds similar to Emily. She told W that her good friends normally call her “Em” anyway, so it worked out.

Diane Keaton

No, Diane and Michael are not related. They are simply both victims of the SAG policy. Diane’s actual legal surname is Hall, just like her iconic character in the movie, Annie Hall. She changed it when joining the union.

Michael J. Fox

Michael kept the majority of his real name but had to add the middle letter. (As his Foundation explains, there was already a “Michael Fox” in SAG.) His given name is Michael Andrew Fox but he chose to go with Michael J. Fox professionally to honor fellow actor Michael J. Pollard.

This post originally appeared at fastcompany.com
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