Jennifer Aniston, Justin Theroux Hold Star-Studded Bash at Beverly Hills Mansion (PHOTOS)

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Jennifer Aniston and her beau Justin Theroux threw a party at their Beverly Hills home on Sunday. And, it wasn’t just your average gathering.

Spotted at the star-studded bash were some of the couple’s A-list pals, including Demi Moore, Ben Stiller, Lake Bell, Ellen DeGeneres, and Portia de Rossi — according to x17.

Celebs dressed down for the deejayed event, but didn’t come empty-handed.

As the party-goers arrived to Theroux and Aniston’s mansion, they came bearing gifts. But, it’s unclear what the gifts were for. There is some speculation that the event was an engagement party, but that’s unconfirmed.

The couple should get used to receiving gifts. Aside from engagement gifts, there are sure to be plenty of wedding gifts in the near future.

In November, one of Aniston’s BFF’s and former Friends co-star Lisa Kudrow admitted that she hadn’t bought wedding gifts for the bride-to-be yet, but she did give her seal of approval to her future hubby.

“Everyone was talking about him back then like, ‘That guy’s cool. He’s really smart. He’s really cool,’” Kudrow told Celebuzz.

Aniston, 43, and Theroux, 41, have been engaged since August after becoming romantically involved on the set of Wanderlust.

What do you think the party was for? Click through the gallery and weigh in below.

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