Google’s self-driving unit Waymo has filed a preliminary injunction against Uber, a few weeks after filing a lawsuit accusing the ride-sharing company of stealing trade secrets related to self-driving technology.

The preliminary injunction asks for all of Uber’s self-driving cars to be taken off the road, effectively halting the company’s self-driving program. Uber has over 30 autonomous vehicles on public roads in Pennsylvania and Arizona.

See Also: Google paces pack in autonomous car race, says California regulator

Waymo alleges that the head of Uber’s self-driving program and former Googler Anthony Levandowski downloaded 14,000 highly confidential files relating to Waymo’s proprietary Lidar technology, before leaving to form Otto, which was acquired by Uber last year.

Lidar is a remote sensing method that measures distance with lasers, a useful tool for self-driving cars that need to know where to go in all weathers. Almost all self-driving vehicles currently tested on the road use the sensor.

A short drive from Google to Otto to Uber?

According to Waymo, Levandowski used the files to build Otto’s self-driving trucks and may have passed the files onto Uber. The transition from Google to Otto to Uber was very short; he co-founded Otto in early 2016 and sold in September for $680 million.

The car-hailing giant has denied the allegations and said they are a “baseless attempt to slow a competitor down.”

It is one of the biggest showdowns in the self-driving industry and could severely affect Uber’s chances of competing, if the trial goes Google’s way. It is also one of the weirder lawsuits, as Google Ventures is one of Uber’s largest backers.