Three years after settling a trade secret lawsuit, electric aircraft company Archer Aviation now owns its former rival, Wisk Aero.

Under the terms of the deal, Boeing has agreed to sell Wisk Aero and two other subsidiaries to Archer in exchange for an ownership stake in the company, according to a regulatory filing released Monday. The other subsidiaries are SkyGrid, a digital airspace and air traffic management software company, and drone maker Insitu.

Boeing will receive newly issued Archer shares equal to 19.75% of Archer’s shares outstanding immediately before closing, resulting in about a 16.5% stake in the company after the deal, according to a regulatory filing and a person familiar with the matter.

The acquisition is a capstone to a once-embittered relationship between two companies developing electric vertical takeoff and landing aircraft.

In April 2021, Wisk sued Archer for “brazen theft” of confidential information and intellectual property. The legal wrangling lasted two years before the companies reached an unusual settlement that not only ended the lawsuit as well as Archer’s counter-suit against Wisk seeking $1 billion in damages, but kicked off a new collaboration. Under the terms of the settlement, Archer agreed to make Wisk the exclusive provider of autonomous technology. Archer also agreed, at the time, to give Wisk the option to purchase up to 13,176,636 shares of common stock at a price of $0.01 per share.

Wisk Aero got its start as Kittyhawk, an electric aviation startup led by Sebastian Thrun, who co-founded the Alphabet moonshot factory X, and backed by Google co-founder Larry Page. Kittyhawk, which shut down in September 2022, had several aircraft programs, including a single-seater, all-electric, vertical take-off and landing vehicle known as Flyer, and Heaviside, a more capable, quieter and once-secret electric aircraft that could fly and land anywhere autonomously.

But it was Kittyhawk’s Cora program that would end up living on. Cora, a two-person, autonomous flying taxi, was spun off in late 2019 into a joint venture with Boeing. The joint venture was renamed Wisk and set out to develop and commercialize electric, self-flying air taxis.

Boeing poured millions into the effort. In early 2022, Boeing invested another $450 million into Wisk. And by 2023, Wisk was a fully owned subsidiary of Boeing.

Meanwhile, Archer, a California-based startup founded in 2018, has expanded its electric vertical takeoff and landing vehicles (eVTOL) program beyond its initial plan to build an air taxi network. The company expanded into the defense sector a couple of years ago, raising a $430 million round in December 2024 to fund its new Archer Defense program. In 2025, it raised another $300 million from institutional investors like BlackRock and Wellington. Archer also struck an exclusive deal with weapons manufacturer Anduril to jointly develop a hybrid gas-and-electric-powered VTOL aircraft for critical defense applications.

Archer, which went public in 2021 through a merger with a blank-check company, continues to make progress on its all-electric Midnight aircraft as well. Earlier this month, Archer completed a piloted round-trip flight between Salinas Municipal Airport and Monterey Regional Airport as the company prepares to begin operations later this year under the White House’s eVTOL Integration Pilot Program.