Archer Aviation Inc. sued Boeing Co., in an escalation of a feud over technology in the race to develop flying taxis.

Archer claims that it has been the victim of a smear campaign by Boeing, via its joint venture with Google co-founder Larry Page. 

Wisk Aero LLC, Boeing’s joint venture with Page’s Kitty Hawk Corp., sought “to halt the forward progress of Archer’s business with flagrantly defamatory public statements intended to destroy Archer’s reputation—including a highly publicized, intentional lie that Archer was under criminal investigation for theft of intellectual property,” the company said in the lawsuit, filed Wednesday in state court in San Jose, California. 

Boeing declined to comment on pending litigation but said it “remains committed to Wisk’s mission of driving innovation and sustainability through the future of electric air travel.”

The lawsuit is the latest round in a battle between Wisk and Archer, who have been fighting over the development of so-called eVTOL—electric vertical takeoff and landing aircraft that will allow consumers to hop over traffic using battery-powered transportation. The global eVTOL market last year was valued at $8.5 billion and will climb to more than $30 billion by 2030, according to Archer. Wisk sued Archer last April, claiming the upstart had stolen its intellectual property. 

The same day the suit was filed, Wisk “launched a vicious media smear campaign aimed at mortally wounding Archer,” according to Archer’s new complaint. The attack was timed before Archer’s listing on the New York Stock Exchange and cost the company up to $1 billion, according to the suit. 

As a partner with Kitty Hawk, Boeing is liable, Archer says, and the lawsuit seeks to “hold it accountable for those wrongs.”

Archer, which originated at the University of Florida and moved to Palo Alto, California, was taken public last year through a merger with a blank-check company led by Ken Moelis. 

The case is Archer Aviation Inc. v. The Boeing Co., 22CV396479, California Superior Court, Santa Clara County (San Jose).