Marc and wife Jennifer Lopez were at a party hosted by Valentino and the Weinstein Company at L.A.'s Andaz Hotel when Marc was spotted cozying up to a sexy brunette — while sitting next to his wife!
"I was shocked when I saw it," says an eyewitness, who adds that Marc and J.Lo weren't exactly affectionate after that.
While Marc's publicist insists that the mysterious woman is a longtime friend of the couple, one thing's for sure — Marc and the lady certainly are chummy!
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