(AP) SAN FRANCISCO – A federal appeals court ruled Monday that former Harvard University schoolmates of Facebook founder Mark Zuckerberg can't undo their settlement over creation of the social networking site. The 9th U.S. Circuit Court of Appeals said Monday that Tyler and Cameron Winklevoss were savvy enough to understand what they were agreeing to when they signed the agreement in 2008. The deal called for a $20 million cash payment and a partial ownership of Facebook. A third classmate, Divya Narendra, was part of the settlement with the twins but did not pursue the second lawsuit seeking to undo the agreement.