A federal judge told Uber that he could bar a top executive from working on its self-driving vehicle program if the company does not more fully investigate accusations that its employees stole intellectual property from Waymo, which was formerly a part of Google.

The ongoing lawsuit embroils two of Silicon Valley’s leading developers of self-driving technology, which experts predict will fundamentally transform transportation in the decades to come. Waymo contends that three former employees took thousands of documents containing trade secrets, then used the information to build self-driving technology now used at Uber, legal documents show.

U.S. District Judge William Alsup instructed Uber to conduct a more exhaustive search for 14,000 documents that were allegedly taken from Waymo.

“This is an extraordinary case, I’ve never seen a record this strong in 42 years,” Alsup told Uber. “So you are up against it. You are looking at a preliminary injunction even if what you tell me is true. What you are telling me is not going to be a get out of jail free card.”

Waymo filed a lawsuit in February seeking to stop Uber from using technology based on intellectual property it claims was stolen. The suit claimed that Anthony Levandowski and two other employees took the documents when they left Google for a self-driving competitor that was later acquired by Uber, where the three now work.

At Wednesday’s hearing, Uber presented details for the first time about its own efforts to investigate the allegations. Arturo Gonzalez, an attorney for Uber, told the court that none of the documents were found on Uber’s servers.

“We can’t produce something that we do not have,” Gonzalez said.

Gonzalez said the company discovered one of the documents on a device allegedly belonging to Sameer Kshirsagar, one of the other employees accused in court documents of stealing trade secrets, Tech Crunch reported. Radu Raduta is the third employee. Levandowski, Kshirsagar or Raduta are not named as parties in the lawsuit.

Uber questioned 85 current and former employees, and searched the computers of 10 of them. The company agreed to search for the documents more extensively after Wednesday’s hearing.

Representatives and attorneys for Waymo and Uber declined to comment or did not respond to interview requests.

On Friday, Uber is expected to outline its argument against Waymo’s request for an injunction that would stop Uber from using the disputed self-driving technology until the case is resolve. The company is also attempting to move the case to arbitration, and a hearing on that motion is scheduled for later this month.

Levandowski previously worked on Google’s self-driving car project, now named Waymo, before leaving to start another autonomous driving company called Otto last year. That firm was quickly acquired by Uber for $680 million and Levandowski now heads Uber’s self-driving car program.

Last week, Waymo also accused Levandowski of working with two competing companies, Tyto Lidar and Odin Wave, while still a Google employee. Tyto Lidar was later acquired by Otto, according to Waymo.

Levandowski has invoked the Fifth Amendment, which protects a person from incriminating himself, and declined to provide information to Uber. He remains an Uber employee.

The outcome of the lawsuit could alter the future of both companies. Waymo and its parent company, Alphabet, have poured large sums of money into the development and testing of self-driving technology. In January, the company announced it had created its own sensors to control the hardware that feeds images and other data to its software.

Uber has moved aggressively to develop and test its autonomous cars on roads in California, Pennsylvania and Arizona. The company poses a threat to Waymo in a marketplace whose competitors already include the world’s largest automakers and other technology companies.

“Competition should be fueled by innovation in the labs and on the roads, not through unlawful actions,” a Waymo spokesperson said previously. “Given the strong evidence we have, we are asking the court step in to protect intellectual property developed by our engineers over thousands of hours and to prevent any use of that stolen IP.”

Industry observers expect that self-driving vehicles will first hit the road as part of ride-sharing fleets, giving Uber and its competitor Lyft a natural advantage over other players. (In 2016, Lyft secured a $500 million investment from General Motors to partner on self-driving efforts.)

The technology could also bring big financial benefits to Uber’s business, which news reports say continues to lose money despite significant growth. Uber shares a portion of the revenue from each ride with its drivers, and that expense could go away over time as its fleet of vehicles becomes more autonomous.

“We are incredibly proud of the progress that our team has made,” Uber has previous said in a statement. “We have reviewed Waymo’s claims and determined them to be a baseless attempt to slow down a competitor and we look forward to vigorously defending against them in court. In the meantime, we will continue our hard work to bring self-driving benefits to the world.”

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