<P> From the first defense of the cup in 1870 through the twentieth defense in 1967, there was always only one challenger . In 1970, for the first time, there were multiple challengers, so the NYYC agreed that the challengers could run a selection series with the winner becoming the official challenger and competing against the defender in the America's Cup match . Since 1983, Louis Vuitton has sponsored the Louis Vuitton Cup as a prize for the winner of the challenger selection series . </P> <P> Early matches for the cup were raced between yachts 65--90 ft (20--27 m) on the waterline owned by wealthy sportsmen . This culminated with the J - Class regattas of the 1930s . After World War II and almost twenty years without a challenge, the NYYC made changes to the deed of gift to allow smaller, less expensive 12 - metre class yachts to compete; this class was used until it was replaced in 1990 by the International America's Cup Class which was used until 2007 . </P> <P> After a long legal battle, the 2010 America's Cup was raced in 90 ft (27 m) lwl multihull yachts in a best of three "deed of gift" match in Valencia, Spain . The victorious Golden Gate Yacht Club then elected to race the 2013 America's Cup in AC72 foiling, wing - sail catamarans . Golden Gate Yacht Club successfully defended the cup . The 35th America's Cup match was announced to be sailed in 50 ft foiling catamarans . </P> <P> The history of the America's Cup has included legal battles and disputes over rule changes including most recently over the rule changes for the 2017 America's Cup . </P>

When did america's cup go to catamarans