Cain tells "Forbes" Perry's recently-hired political consultant Curt Anderson leaked the story to Politico.
Cain says he told Anderson of the sexual harassment claims in 2003 when they worked together on Cain's failed U.S. Senate campaign.
Both Anderson and the Perry campaign deny any involvement in leaking the story.
It's centered around two former female employees of the National Restaurant Association.
They were reportedly given settlements after accusing Cain of inappropriate behavior.