The 42-year-old was on stage at the Oscars presenting an award with Cameron Diaz when her typically J.Lo-esque (i.e. low cut and gold) gown revealed a little bit of nipple.
Or did it?
US TV show host, Carson Daly, seemed pretty sure of what he saw, tweeting: 'Dear JLo, your left nipple is out. K, bye. Xoxo carson,' but the topic's certainly been up for hot debate!
Check out the clip above and tell us your verdict.
Hilariously, J.Lo's nipple acquired its own Twitter account within minutes of the incident (@JLosNipple ) so you can too can contribute to the Con-tweet-versy…