Jennifer Aniston and boyfriend Justin Theroux went public with their relationship in July last year

Justin Theroux hosted a birthday party for girlfriend Jennifer Aniston in a penthouse last weekend.

The loved-up actor, 40, rented out a suite overlooking West Hollywood's Sunset Strip and hired staff to serve appetizers to the guests, who included Courteney Cox, 47, and Ben Stiller, 46.

'There was minimal decor with white hurricane candles lining the room and the balcony,' says an insider.

'A bar was set up inside along with a table where guests put presents.'

Jen, now 43, wore a black dress for the occasion and stayed until late with her smitten man, who she met on the set of new movie Wanderlust.

'She never got too far from Justin,' the insider tells Us Weekly.

'Every once in a while, Justin would come up from behind and give her a big hug and kiss.

'They would embrace and whisper to each other for a minute but then go back to socialising.' 

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