Eight key changes to the America's Cup

Emirates Team New Zealand competing in the 34th America's Cup. Photo / File.

Nearly eight months on from Oracle's spectacular defence of the 34th America's Cup, the US syndicate has finally released the Protocol for the next event in 2017.

Originally expected to be announced in late March, many of the more controversial elements of the 78-page Protocol had been sign-posted well before today's release.

Despite the debate over the shape the new format was set to take, it does not appear Oracle have budged of any of the contentious points of the new set of rules.

The key changes for the 35th America's Cup match are:

- Organisers are predicting there will be 6-8 challengers in the next event, but only the top four will race in the America's Cup proper. With no guarantee they will compete in the main event, this may deter teams from entering.

- Unlike in previous America's Cup regattas, the defender will be allowed to sail against challengers in the early elimination rounds.

- An America's Cup World Series in 45-foot catamarans in 2015 and 2016 will be used to seed the America's Cup qualifiers, a double-round robin event. The winner of the qualifiers - whether it's Oracle or a challenger - will get a bonus point in the America's Cup match.

- The top four challengers will race in the America's Cup playoffs - the semifinals and finals - with the winner facing Oracle in the match. However, the challenger that earns the bonus point for the America's Cup match could be eliminated before reaching the ultimate round.

- The America's Cup match will be sailed in 62-foot wing-sailed foiling catamarans, requiring only eight crew. Last year's America's Cup was sailed in 72-foot catamarans, with 11 crew members.

- New nationality rules require two of the eight crew on the 62-footers and one of the five crew on the 45-footers be from the home country of a team's backing yacht club.

- Oracle can build two 62-foot, wing-sailed foiling catamarans, insuring against a catastrophic failure, while challengers will be limited to one - a clause that's sure to be controversial.

- A venue for the 35th America's Cup has not yet been announced, with the organisers still considering pitches from San Francisco, San Diego, Bermuda and Chicago to host the main event. It is unlikely the venue will be confirmed before the August deadline for challengers to enter the next event.

The stalling over making a decision on venue is a key bugbear for the commercially-funded teams like Team New Zealand, who will struggle to get a commitment from sponsors until the venue is known.