George Clooney has quietly withdrawn from the Writers Guild of America after the union rejected his request for a writing credit on his new film “Leatherheads,” Daily Variety reported in its Friday edition.

Clooney opted to become a “financial core status” nonmember last fall, which means that he is still covered by the basic contract, the trade paper said.

But he loses his voting rights, and cannot run for office or attend membership meetings, according to the WGA’s constitution. He must continue ...