Electric vertical takeoff and landing (eVTOL) aircraft developer Archer Aviation has filed a patent infringement complaint against fellow eVTOL manufacturer Vertical Aerospace.
California-based Archer is claiming that Vertical's ‘Valo’ aircraft is illegally copying design aspects of Archer's ‘Midnight’ aircraft. Vertical is based in Bristol, UK.
Vertical revealed its new Valo design in December last year, replacing its VX4 prototype. The VX4 project was formally announced in 2020 before its design was unveiled in the summer of 2024.
“After years of developing its VX4 aircraft, Vertical has abandoned that design and unveiled a new aircraft, Valo, which is a visual ‘mimic’ of Archer's Midnight aircraft's award-winning industrial design,” said an Archer spokesperson.
The filing said: "Vertical has knowingly, willfully, and in reckless disregard leveraged and exploited the substantial goodwill and reputation associated with Archer’s patented designs… Vertical’s infringement is readily apparent from a visual comparison of the overall appearance of the Valo to Archer’s patented designs.”
However, Vertical has denied the claims, stating Archer's complaints are “without merit” and that it will “defend those claims vigorously”. The company also stated that Archer's complaints are “merely an attempt to district from the challenges Archer is facing competing in the marketplace”.
“Vertical’s aircraft architecture, proprietary technology stack and certification pathway have been independently developed over many years and are protected by a robust portfolio of intellectual property rights,” said Vertical Aerospace chair Domhnal Slattery. “Our focus remains firmly on execution and certification. That is where sustainable value is created - and that is where we are leading.”
The complaint was filed in the Eastern District of Texas on Monday (February 23) — the same day Raymond James downgraded Vertical's rating from hold to sell. Raymond James analyst Savanthi Syth cited liquidity concerns and its ability to raise capital, adding that the company would need to raise capital soon.
Syth noted that the agency has a “lot of respect” for Vertical, citing their transparency and the progress made in a more strict aviation regulatory environment.
“Given enough time and money, we believe Vertical would be successful, but the market has soured on higher-risk ventures lately,” said Syth.
Vertical's stock fell sharply following the analysis.
Raymond James maintained Archer Aviation as its only outperform-rated eVTOL stock, citing its relative valuation and less capital-intensive model.
Last week, Archer Aviation selected Bristol as the home of its UK engineering hub — encroaching on Vertical Aerospace's territory.
Raymond James said this increased the risk of Vertical losing engineering talent to its competitor.
Specifically, the suit claims that Vertical infringed on “at least two” of Midnight's design patents and one utility patent.
The design patents cover Midnight's V-tail, fuselage and wing configurations, while the utility patent covers flight control systems and ‘control allocation’ methods that manage electric propulsion units and battery power on its tilting architecture.
Archer provided a visual comparison from the filing, seen below:
Vertical said it has “developed a robust aircraft design with a clear path to certification, underpinned by Vertical's proprietary and market-leading technology and international IP portfolio.”
Archer further claimed that Vertical's unveiling of Valo and promotional events in US cities — New York City in January 2026 and Miami earlier this week — bore a “strikingly similar” resemblance to Archer's own events held in the same cities last year.
In July last year, Vertical completed its first airport-to-airport flight with its VX4 prototype.
In December 2025, Archer had submitted multiple applications with US city partners to launch air taxi operations under a new federal eVTOL scheme, with Washington setting out a pathway for advanced air mobility (AAM) to enter commercial service.