Oh, Shia -- don't you know gentlemen never kiss and tell?
We can't deny it's a juicy scoop -- especially because he wouldn't say if she was involved with her now-husband, Brian Austin Green, at the time -- but E! Online describes the kiss-and-tell moment as "kinda douchey."
"Look, you're on the set for six months, with someone who's rooting to be attracted to you, and you're rooting to be attracted to them," the 25-year-old says in the new issue of Details magazine after nodding "affirmatively" when asked if he and Fox hooked up.
"I never understood the separation of work and life in that situation. But the time I spent with Megan was our own thing, and I think you can see the chemistry onscreen," he continues.
LaBeouf, who has since said he needs to learn to "edit" himself more, also talked about "philandering around" with his "Transformers: Revenge of the Fallen" co-star Isabel Lucas and dished that his date with Hilary Duff was "probably the worst date either of us has ever had."
Ladies, steer clear of this one!