The twin brothers who accused Facebook Inc and founder Mark Zuckerberg of stealing their idea for the social networking website lost their bid to have a U.S. court void a multi-million dollar settlement of their claims.

Cameron and Tyler Winklevoss failed to convince the 9th U.S. Circuit Court of Appeals in San Francisco to reconsider its April 11 ruling upholding the $65 million cash-and-stock settlement they reached with Facebook in 2008.

The brothers had complained the settlement was fraudulent because Facebook hid information from them. They also said they should have received more Facebook stock.

Without providing a reason, the court declined to have an 11-judge panel review the original ruling, which had been made by a three-judge panel.

Jerome Falk, a lawyer for the brothers, said in a statement that he plans to appeal to the U.S. Supreme Court.

Facebook spokesman Andrew Noyes said in an email that the company was pleased with the court's decision.

The identical twin Winklevosses were classmates of Zuckerberg at Harvard University and are rowers who competed in the 2008 Beijing Olympics. Their feud with Zuckerberg was dramatized in the 2010 film The Social Network.

A revised accord could enable the Winklevosses to benefit from Facebook's rising market value, which private investors have said in recent weeks might top $70 billion.

But in his April ruling, Chief Judge Alex Kozinski had called the brothers sophisticated parties who, with a team of lawyers and a financial adviser, had reached a quite favorable settlement.

In a separate lawsuit, New York businessman Paul Ceglia is claiming he had a contract with Zuckerberg that entitles him to 84 percent of Facebook.

The case is Facebook Inc et al v. ConnectU Inc et al, 9th U.S. Circuit Court of Appeals, No. 08-16745.

(Reporting by Jonathan Stempel; editing by Andre Grenon and Carol Bishopric)