Los Angeles County jail records show Marston Hefner was released Monday after posting $20,000 bail.
Police Lt. Rick Aversano told the Los Angeles Times that police were called Sunday to the Pasadena home and arrested Hefner after determining his girlfriend had minor injuries consistent with an assault.
Marston Hefner is one of two adult sons of the Playboy founder and his former wife, ex-Playmate Kimberly Conrad Hefner.
It was not clear whether he has hired an attorney. He could not be reached for comment, and the arrest was not addressed on the Twitter accounts of Hugh, Marston or brother Cooper Hefner.
