Archer Aviation Inc. secured three Boeing subsidiaries—Wisk Aero, SkyGrid and Insitu—in a deal announced Monday, advancing the company's push into aerospace and defense through autonomous flight and drone technology.

Under the agreement, Boeing will receive a 20 percent stake in Archer, warrants and the right to nominate one director to Archer's board. A collaboration and technology-sharing arrangement gives Boeing continued access to Wisk's autonomous flight technology for its commercial and defense aircraft programs.

Archer's stock rose 20 percent following the announcement. Shares of rivals Joby Aviation and EHang Holdings were largely unchanged, signaling a company-specific reaction rather than a sector-wide move.

The acquired units expand Archer's capabilities across three areas: Wisk Aero, Boeing's automated air taxi program; SkyGrid, an air traffic management software provider; and Insitu, a drone manufacturer.

Boeing retains access to Wisk's core autonomous flight technology under the collaboration terms, meaning Archer's advantage in that domain is not exclusive. The deal allows Boeing to monetize the subsidiaries while preserving a direct link to the underlying technology.

The integration of Wisk's autonomous systems, SkyGrid's air traffic software and Insitu's drone hardware positions Archer to compete across both commercial urban air mobility and defense applications.