When Jack Gillis married Meg White, he did what he considered a very progressive thing: he took her last name in the marriage. That’s how we got Jack White.
When Sum 41’s Deryck Whibley married Avril Lavigne in 2006, he (unbeknownst to just about everyone), did the same thing. Deryck Whibley legally became Deryck Lavigne. (Or, according to some sources, Deryck Lavigne-Whibley.)
He remained Deryck Lavigne(-Whibley) even after the divorce went through. But this week, more than three years later (and after Avril married Nickelback’s Chad Kroeger), he’s filed papers to go back to being Deryck Whibley.