The two joined a group of 12 people for an industry dinner party honoring their manager Cynthia Pett-Dante's birthday. "They hugged and kissed when they greeted each other," says an onlooker. "They talked for a while."
While the pair, who have remained friendly since Pitt's split from Aniston six years ago, didn't sit next to each other at the table, they still spent a good portion of the evening enjoying one another's company.
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"They were chatting, catching up," adds the onlooker. "They both seemed happy and totally relaxed, very at ease. And they were both smiling the entire time. It didn't seem awkward at all."
Pitt enjoyed a steak and beer, and he sat at the bar at one point with other patrons. "He was really cool."
Eastbound and Down star Danny McBride also attended the dinner.