America's Cup: Emirates Team NZ fires broadside at North Sails over sail patent
by Richard Gladwell Sail-World NZ 18 Sep 06:47 PDT
Emirates Team NZ - Day 21 - August 15 2026 - Auckland, NZ © Sam Thom/America's Cup
Emirates Team New Zealand CEO, Grant Dalton has issued a strong response to reports from USA of Court action by North Sails over a sail design patent that has been granted to the five-time America's Cup champions.
On Tuesday, September 15, North Sails, a Delaware-registered company, filed a 31-page brief in the US Court in Eastern Virginia to overturn the previously reported patent granted to Emirates Team NZ and its sail designer Dr Steven Collie.
The gist of the North Sails case is that "under the supply agreements between North Sails and the [America's Cup] teams, at the end of each competition, the
information that the teams obtained during sail development—thanks to the use of North Sails’ equipment, software, confidential information, and know-how—is shared with all participants and with North Sails in a so-called “collective design debrief.”
Collie has a PhD in Mechanical Engineering (PhD), a product of Auckland University's renowned Yacht Research Unit, his doctoral research focused on the application of Computational Fluid Dynamics (CFD) and experimental wind-tunnel validation for downwind yacht sail aerodynamics. His core technical specialisation included advanced CFD, Fluid-Structure Interaction (FSI) modelling, multiphysics simulations, and aero-elastic deformation. His work bridges virtual aerodynamic code with structural composite mechanics to predict how flexible sails and wings deform under high-velocity aerodynamic loads.
He has over 20yrs of America's Cup experience beginning with the 2007 America's Cup in Valencia in the IACC monohulls, progressing through the AC50, AC72 and AC75 America's Cup eras, with three Cup wins to his credit. He has worked with hard wingsails and the soft double skinned fully battened sails used in the AC75.
North Sails claims that the matters covered in the patent granted to Collie and Team New Zealand were in fact first developed by a North Sails designer, Matt Savage. North Technology objected to the patent being granted to Dr Collie/Team New Zealand; however, these objections were overruled.
The Brief accuses the five-time America's Cup champions of "stealing North Sails’ proprietary information and inventions, patenting them as their own, and then weaponising the resulting patents to threaten North Sails and its customers on the eve of the 38th America’s Cup."
Kiwis push back
The North Sails' missive triggered a stiff rebuke from the New Zealand team, now working towards the second Preliminary Regatta in Naples.
“We have not yet been served with any filings, although we have only just become aware of them," said Emirates Team New Zealand CEO Grant Dalton, en route to Dubai, when asked by Sail-World for comment on the US legal reports.
"Emirates Team New Zealand absolutely disputes the claims that appear to have been made."
"From what we know it appears to a spurious attempt by North Sails to intimidate and pressure a team who has valid patents in their markets in US and Europe."
"North Sails have been aware of the patent for more than five years, have been making Emirates Team New Zealand sails using our technology for several campaigns, have unsuccessfully challenged the patent in the US via a Post Grant Review process, but never raised ownership."
"In fact, they have contractually acknowledged that Emirates Team New Zealand owns the patent, and this filing is presumably a response to arbitral legal proceedings taken against Norths in NZ over the misuse and breach of the patent in sails made for other Teams."
"North Sails is owned by Oakley Capital, which in turn is the majority owner of Team GB1, which is competing against Emirates Team New Zealand in the 38th edition of the America's Cup in 2027. Team GB1 has sought to use the patent through a protocol change and was unsuccessful.”
Expected to share
A recurring theme throughout the North Sails' Brief is their view that the "long-standing sharing of North Sails’ software, technology, and design staff,
naturally gave rise to the expectation that no team would attempt to claim exclusive patent rights based on projects developed for participation in the event."
"Against this background, TNZ has been the center of an unprecedented rift by filing for the Collie Portfolio, refusing to take part in the collective design debrief following the 36th America’s Cup, and threatening infringement actions against North Sails and the rival teams," Norths say.
One of the pillars of the North Sails' Brief is the expectation that team designers would sit down at the end of an America's Cup Match and share their learnings, calling this debrief a "reset event".
Team New Zealand have a reputation and culture of fiercely guarding their engineering thinking and intellectual property. That ethos goes right back to their first America's Cup Challenge in 1986/87, where the team built the first and only fibreglass 12 Metres, and was followed by the development of a foiling AC72 in 2013; the use of cyclors in 2017; and the development and refinement of the AC75 in 2021-2024.
It is not possible to break out components like sail design from the integrated AC75 package, without revealing details and design concepts about other components such as mechatronics, flight control etc which are outside the ambit of North Sails software applications. No serious America's Cup team will reveal that information to other teams, enabling them to fast-track their early design direction, when key decisions have to be made. Team New Zealand are also in a unique position where it sells its designs and intellectual property to startup teams, going back to Luna Rossa in 2012/13, K-Challenge in 2024 and 2027, and Team Australia in 2027.
The America's Cup context is quite different from other classes such as IRC or One Design racing, where Norths are selling a product and their design experience to an owner.
"North Sails has always relied upon and enjoyed a culture of collegiality, cooperation and trust with the teams and their members who are licensed to use the NS Design Suite," the Brief says. "The design debrief at the end of the America’s Cup cycles serves as a reset event. North Sails’ belief is that this culture of cooperation benefits the sport and all the individuals who invest their time and resources in the sport."
"While there is often a brief period of reluctance to share hard-won sail design lessons during the design debrief, there was never a case of any team reneging on the agreement to share its design information until TNZ announced it would not abide by its prior agreement to participate and refused to participate in the America’s Cup 36 design debrief."
"At the same time that TNZ refused to participate in the debrief, Collie and TNZ betrayed the trust of the community further by filing a patent application on what they had learned through use of the NS Design Suite for America’s Cup 36. In doing so, Collie — with the knowledge of TNZ—violated his confidentiality agreement and misused North Sails’ confidential information and inventions to file patent applications naming only Collie as
inventor. Now that these applications have matured into a U.S. patent and foreign counterpart patents, TNZ is attempting to gain a competitive advantage in the America’s Cup 38, not through sailing skill, but through use of these misbegotten patents."
Challengers warned
Last week, America's Cup Challengers were warned by Emirates Team New Zealand that they were taking a legal risk over possible infringement of a sail design/engineering patent owned by Emirates Team New Zealand, relating to how AC75 sails are designed and manufactured.
The documents were leaked to Sailing Illustrated, a twice-weekly live sailing webcast, and include correspondence bearing the North Sails logo and a legal firm representing Emirates Team New Zealand, along with the patent document, and reveal that the team intended to enforce a patent it held over sail design.
North Technology has contested whether the patent is a unique development and suggested a workaround - manufacturing the sails for the Challengers at its Sri Lankan facility, a country it says is outside the patent territories of the USA and Europe.
After the 2017 America's Cup win in Bermuda in foiling 50ft wingsailed catamarans, it was Team New Zealand's design team who spent several million dollars developing the AC75 foiling monohull concept, including the use of a double-skinned mainsail, and the need for sails that were capable of working across a much broader wind range than conventional monohulls and sail technology. In the previous three editions of the America's Cup, teams used hard wingsails instead of soft mainsails, and in the 2017 America's Cup, sail designers were redundant because all jibs were one design supplied by North Sails.
A significant part of this design exercise was the conduct of various feasibility studied by Emirates Team New Zealand to verify that their AC75 concept would actually sail - something that was doubted by many until the launch by the New Zealand team of the prototype Te Aihe in Auckland, in September 2019.
For the earlier story sail-world.com/news/299654