Michael Egan III sued Garth Ancier on Monday in Hawaii, accusing Ancier of abuse in 1999 when Egan was 17.
An email message sent to Ancier was not immediately returned. Egan also sued two others in separate lawsuits Monday, claiming they also abused him on trips to Hawaii.
No criminal charges have been filed against any of the men sued by Egan.
Egan, now 31, said last week that he was abused by Singer and others starting when he was 15, and given drugs and promises of a Hollywood career.
Singer's attorney Marty Singer has denied Egan's accusations and has said the director wasn't in Hawaii in 1999 when the alleged abuse took place.