Chris Brown Doesn't own Rihanna's Lady Parts "Its only a song"

Chris Brown is backing off last week's proclamation that he is sole and rightful owner of Rihanna's lady parts ... telling TMZ, "It's a song ... it's a song ... that's all it is."

Brown was leaving Lure nightclub in L.A. this weekend when we brought up the statement he made at the Emerson Theater last week ... when he gave the crowd a quick lesson about how to talk to women.