Joby is buying a stealth-technology firm for $500m, and rebuilding its defence arm around it

Joby Aviation has agreed to buy Resonant Sciences, a Dayton, Ohio radar and low-observability specialist, for about $500m, in the largest acquisition the electric air taxi company has made and the clearest signal yet of where it expects its near-term revenue to come from.

The structure is $450m in cash and roughly $50m in Joby common stock priced at signing, with some Resonant employee-shareholders taking equity so they retain an interest in the combined business.

There is no earnout, which is worth noting because headline figures on deals this size often bundle one. The seller is Cerberus Capital Management, which invested in Resonant in 2023. Closing is expected in the first half of 2027, subject to regulatory review.

Founded in 2015, it employs about 250 people across Ohio, Virginia, West Virginia, Michigan, Colorado, and North Carolina, and designs radio-frequency and mission systems: advanced apertures, electromagnetic measurement, electronic countermeasures, instrumentation radars, and the frequency-selective radome and antenna work that sits underneath low-observability aircraft design.

More than 90% of its staff hold security clearances and the company is facility-clearance accredited, selling directly to the US government and to prime contractors.

It also makes money, which Joby does not. Resonant turned over more than $100m in the trailing twelve months, up around 40% year on year, at adjusted EBITDA margins in the high teens.

First-half bookings more than tripled against the same period in 2025 and its backlog more than doubled. Joby, by comparison, booked $63m of revenue in the first half of this year and burned $318m in operating cash, according to Motley Fool’s reading of its filings.

“Resonant has built an exceptional business that combines advanced technology, vertically integrated production capabilities and deep customer trust,” said JoeBen Bevirt, Joby’s founder and chief executive.

He framed the logic as additive rather than defensive: “This gives us the ability to do projects that Resonant couldn’t do alone and Joby couldn’t do alone.”

After closing, Resonant keeps its name and becomes Joby’s dedicated defence unit under co-founder and chief executive J. Micah North, absorbing Joby’s existing military work on turbine-electric and hydrogen-electric aircraft and autonomy.

The combined Ohio footprint will run to roughly a million square feet, most of it near Wright-Patterson Air Force Base, home of Air Force Materiel Command and the service’s life-cycle management centre. Proximity to the customer is doing some of the work here.

Joby already has defence business. It has flown aircraft to Edwards and MacDill under the Air Force’s Agility Prime programme, on a contract extended in 2023 to a total value of $131m, and last year flew an autonomous hybrid VTOL demonstrator built with L3Harris.

What it does not yet have is FAA type certification for the aircraft that the company was founded to build, though it remains the furthest along of anyone in the process, and it has been flying between JFK and Manhattan in seven minutes on demonstration runs while it waits.

Investors did not treat the announcement as good news. Joby shares fell on Tuesday, though by how much depends on when you look: roughly 4.4% to $8.42 on one intraday reading, about 6% on another, and 6.5% in premarket.

Liquidity drops from around $2.3bn to an estimated $1.85bn once the cash goes out.

The wider air-taxi sector has been slipping its timelines for years while certification regimes catch up. Buying a cleared, profitable defence contractor is one way to stop waiting. Joby now expects to close in about ten months.

It is the second time in a year that Joby has bought its way into a revenue line rather than waiting for one.

Last August it agreed to acquire Blade Air Mobility’s passenger helicopter business for up to $125m, giving it routes and customers before it had an aircraft certified to fly them.

It has also been flying a demonstration network in Dubai, where it is targeting commercial launch this year. The pattern is consistent: acquire the operating business now, certify the aircraft later.