Electric aircraft manufacturer Archer Aviation has filed a countersuit against rival Joby Aviation in California federal court, alleging that Joby concealed its business relationships with Chinese entities and defrauded the U.S. government.

The countersuit represents an escalation in a legal battle between two prominent companies developing electric vertical takeoff and landing aircraft for commercial passenger service. Archer's filing comes approximately four months after Joby initially sued Archer for alleged corporate espionage.

According to Archer's countersuit, Joby failed to properly disclose its reliance on Chinese business partnerships and suppliers while pursuing U.S. government contracts. The lawsuit specifically accuses Joby of downplaying its connections to China in dealings with federal agencies.

Both companies are among the leading developers in the emerging electric air taxi market, competing to bring their aircraft to commercial operation. The legal dispute highlights tensions in the industry as companies navigate regulatory approval processes and seek government support while managing international business relationships.

The case is being heard in federal court in California, where both companies are headquartered. Neither company has provided detailed public responses to the specific allegations in the ongoing litigation.