Reuters:

Casiraghi, 24, the grandson of former Hollywood actress Grace Kelly, was briefly hospitalized after the incident, according to media reports. Police said he and three other men were struck by former restaurateur Adam Hock in a dispute at The Double Seven club about 2 a.m. on Saturday.
Among those punched was Stavros Niarchos, the Greek shipping scion and former boyfriend of hotel heiress Paris Hilton, according to a criminal complaint.
Casiraghi told police he was repeatedly struck in the face, according to the criminal complaint, "creating a laceration on informant's cheek, and causing bruising, swelling, redness and substantial pain to informant Casiraghi's face."
Comments
Poor little rich boys
February 20, 2012 by Angelo Arvanitis (Canada ), 12 weeks 5 days ago
Acting like jerks got what they deserved... Too bad their daddies where not there to get the same treatment for raising a bunch of spoiled pansies!