Ben Ainslie’s hopes of skippering a British entry in the next America’s Cup will rest on whether two billionaires can come to an agreement over the format of the next contest.

A New York court has ruled that BMW Oracle, the American team owned by Larry Ellison, are the Challenger of Record for the 33rd America’s Cup to Alinghi, the Swiss team owned by Ernesto Bertarelli.

Oracle won the latest and final court ruling over whether a Spanish club, Náutico Español de Vela (CNEV), who had been chosen by Alinghi as their preferred challenger, were a bona fide club.

Alinghi defended the Cup in 2007, having won it in 2003, but Oracle dispute the authenticity of CNEV, who had not held a proper regatta, as required by the Deed of Gift that governs the 150-year-old competition. The legal battles have been going on for 18 months.

The decision by the New York Court of Appeals yesterday means that the next Cup could be decided by a best-of-three battle in huge multihull boats between Alinghi and Oracle if Ellison and Bertarelli cannot come to an agreement about how else it should be contested.

This would rule out Team Origin, the British team helmed by Ainslie, the triple Olympic champion, and the 16 other teams who want to compete for the trophy. “It has consistently been our view that the America’s Cup should be fought on the water,” Alinghi said in a statement. “Today through the courts Oracle has won the right to challenge Alinghi.”

It is understood that Bertarelli has contacted Ellison to see whether a multiboat regatta is possible. This would have to be in smaller boats than the 90ft trimaran that Ellison specified in his challenge.

The American team are considering the court’s ruling and will make their intentions clear in the coming days. “Anything is possible with mutual consent,” BMW Oracle said.

The court in its ruling called on the clubs backing the two teams to “work together to maintain this noble sailing tradition as a perpetual Challenge Cup for friendly competition between foreign countries”.