The X-Men director made headlines in April when Michael Egan, a former aspiring actor, accused Singer and three other Hollywood figures of molesting him when he was underage.
An anonymous British plaintiff, known as John Doe 117, followed with a similar complaint in May. Singer, who denies all allegations, has previously filed a motion asking the Hawaii District Court to dismiss Egan's accusations.
As BuzzFeed previously reported, Singer and a person who appears to be Doe were photographed together during the London premiere for Singer's Superman Returns in 2006.
Singer's motion also asks that Doe pay at least $300,000 towards Singer's legal fees, which are expected to be "exorbitant."
Jeffrey Herman, the attorney for both Egan and Doe, did not immediately respond to requests for comment. A representative for Singer also did not immediately respond to requests for comment.