Archer Aviation has acquired the IP of defunct eVTOL developer Lilium, emerging triumphant from a competitive auction for about 300 patent assets that formerly supported the German company’s ducted-fan aircraft program. The companies confirmed the €18 million (about $21 million) deal, which suggests that while Lilium’s operations are winding down, its engineering ideas will shape what comes next for electric aviation.
Archer edged Ambitious Air Mobility Group and U.S.-based Joby Aviation, the latter of which confirmed it had bid. The sale capped an administrator-led sales process following Lilium’s insolvency, a denouement to a high-profile journey that had seen more than $1 billion in fundraising since 2015 and made its second-generation airplane the first of Europe’s new generation of electric aircraft when it flew last May, attracting backers from Tencent TECDY along with early customer interest out of the Middle East.
Why Archer needed the patents Lilium once held
For Archer, it’s all about optionality, leverage, and time-to-market. The new addition is said by the company to cover high-voltage power distribution, flight controls, electric ducted fans, and advanced airframe concepts — competencies that directly sum up to eVTOL’s most challenging technical bottlenecks: power density, thermal management, noise, and failure tolerance.
Archer’s current aircraft, the Midnight, employs an open-rotor design similar to the Lilium or Vertical take-off and landing craft with a combination of lift and tilt propellers designed for short urban hops. Lilium is effectively on the other end of the spectrum, with a proposal that tends toward compact ducted propulsion that leans on higher-speed cruise and diagnosing interior noise at the airframe level in the patent language. That contrast leaves Archer plenty of room to mess around with lateral missions — hops between regions, logistical challenges, or niche government assignments — without having to start from scratch.
The company has also expanded beyond urban air taxis. After going public in 2021, Archer landed a defense program with Anduril to co-develop hybrid VTOL systems for sensitive applications. For defense, ducted propulsion and high-voltage power electronics may be of particular interest when acoustic signatures, debris ingestion avoidance, and compact packaging are important.
What the acquired Lilium patent portfolio covers
Engineers at Lilium spent years trying to solve the trade-offs of distributed, ducted electric propulsion — incorporating dozens of fans into wing and canard surfaces while controlling for heat and power. Patents in this field usually focus on tip-clearance control, diffuser geometries, vibration attenuation, or fault isolation. Anticipate crossover with battery and inverter thermal management, as well as redundancy in flight–control laws for multicopters.
Archer says the purchase brings its global IP assets to over 1,000, a pretty hefty defensive moat in an industry that has already seen some hotly contested IP spats. “He who controls the patents controls the market” has been a somewhat cynical phrase since it was uttered by Airbus at launch, but industry observers will recall the skirmishes between big eVTOL players in recent years; even if all it does is buy freedom to operate, strengthen licensing posture, and expedite certification by locking down design choices early, a meaty patent wall delivers that capability at scale.
It is also a practical way to collapse R&D cycles. Instead of reinventing every subsystem, Archer can pick and choose which proven ideas it incorporates into its technical roadmap — especially in high-voltage distribution and control software, where the reliability proof point is often worth just as much to regulators as the patent.
Implications for the eVTOL race as consolidation looms
The handoff points to a broader truth: consolidation is coming to advanced air mobility. Based on interviews with aviation consultancies and public investor materials, the sector has drawn well over $10 billion in investment since the latter half of the 2010s, but certification and infrastructure timelines are stretching out, while only a few manufacturers will likely scale their production. In that scenario, assets from failed programs will be recycled by those best-capitalized.
Regulatory momentum is building in both the United States and Europe. The EASA SC-VTOL concept is reaching maturity, while the FAA has defined power-lift certification paths and granted crucial operational approvals — all of which coalesce to focus designs toward certifiable concepts. Hence patents related to redundancy, controllability in transition, and energy reserve margin are also strategically important.
For Joby, which confirmed that it participated in the bidding, the development is a reminder of the fact that IP positioning remains an active front. Joby’s own airframe has a tilt-rotor propulsor bias; winning ducted-fan expertise would have expanded its option set. The card is now in Archer’s hand, and could potentially have some bearing on any future cross-licenses or supplier partnerships that come about as the market continues to consolidate.
What to watch next as Archer integrates Lilium IP
The short-term question now is whether Archer integrates some of the ducted-fan technology into a derivative airframe or keeps the portfolio largely for defensive and licensing purposes. Ducted fans can bring community-noise benefits in cruise and a smaller geometry for wing integration, but they add structural weight and can be less efficient in hover relative to open rotors — trade-offs that require new validation against today’s batteries and power electronics.
Another signal will be Archer’s dialogue with regulators and suppliers. After all, if you start seeing Lilium’s high-voltage or flight-control IP showing up in certification artifacts and supplier specs, that’s going further down the road. Industry watchers should also be on the lookout for alliances on regional mobility or defense — markets where ducted architectures could really fly.
Lilium’s tale extends beyond the last balance sheet entry. Its engineering wagers — some daring, some contentious — are now in Archer’s expanding toolkit. In a race that’s capital-intensive and in which time and proven ideas are currency, this unassuming transfer could ultimately prove more significant than a splashy product unveiling.