Livingston, whose most notable film credits include "Swingers" and "Office Space," reportedly filed the lawsuit in Los Angeles on Friday. He cited libel, invasion of privacy and using his name and likeness without his permission.
According to the papers obtained by TMZ, an alleged Wikipedia hacker has been continuously changing Livingston's Wikipedia page since May to say he is dating a man named Lee Dennison.
Every time Livingston's camp corrects the information, the alleged hacker "changes them back almost immediately," according to the lawsuit.
Furthermore, the actor claims the hacker also created phony Facebook profiles for himself and Dennison, with both pages noting the two men were in a relationship together.
Livingston, 42, married actress Rosemarie DeWitt on November 2, 2009 in San Francisco.
He most recently appeared in the film "The Time Traveler's Wife," starring Eric Bana and Rachel McAdams, earlier this year.
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