Tesla has filed a lawsuit against Rivian claiming that it has stolen trade secrets and intentionally poaches employees to gain insider info. The world’s leading electric-vehicle maker alleged that four of its former workers took highly sensitive proprietary information as they left to work for the rival startup, and Tesla said it suspects there are at least two more culprits. “Misappropriating Tesla’s competitively useful confidential information when leaving Tesla for a new employer is obviously wrong and risky,” according to the complaint filed in state court in San Jose, California. “One would engage in that behavior only for an important benefit — to use it to serve the competitive interests of a new employer.”

Rivian — which counts Amazon.com, T. Rowe Price, BlackRock Inc., and Ford among its top-tier investors — denied the allegations. The company said it requires all new employees to confirm “that they have not, and will not, introduce former employers’ intellectual property into Rivian systems.” “Rivian is made up of high-performing, mission-driven teams, and our business model and technology are based on many years of engineering, design, and strategy development,” the company said in an emailed statement. “This requires the contribution and know-how of thousands of employees from across the technology and automotive spaces.”

Tesla has previously sued former employees for allegedly taking its trade secrets to China’s Xpeng Motors and Silicon Valley-based Zoox Inc. In the new suit, Tesla called itself Rivian’s “number one target from which to acquire information,” and said that Rivian has hired 178 ex-Tesla employees, roughly 70 of whom joined Rivian directly from Tesla. Rivian said in its statement that “we admire Tesla for its leadership in resetting expectations of what an electric car can be,” while calling the claims in the lawsuit baseless and “counter to Rivian’s culture, ethos and corporate policies.” The case is Tesla Inc. v. Rivian Automotive Inc., 20CV368472, California Superior Court, Santa Clara County (San Jose).