Courteney Cox and David Arquette
12/01/2010 AT 11:45 AM EST
Though they reunited
for a family bowling outing in November, on Monday, it was all business for Courteney Cox
and David Arquette
as they lunched together with three associates at Morton's the Steakhouse in Burbank. They arrived and left separately, though Arquette kissed his estranged wife on the cheek when she entered the restaurant. "They were very cordial and friendly," an onlooker tells PEOPLE.