Waymo, the self-driving car company spun off late last year by Google, is suing Uber and its self-driving truck company Otto, claiming the ride-hail giant stole its key technology.

According to a lawsuit filed today in federal court in California, Waymo accuses Anthony Levandowski, an engineer who left Google to found Otto and now serves as a top-ranking Uber executive, stole 14,000 highly confidential documents from Google before departing to start his own company. Among the documents were schematics of a circuit board and details about radar and LIDAR technology, Waymo says.

In a Medium post, Waymo goes into greater detail about its allegations against Levandowski:

We found that six weeks before his resignation this former employee, Anthony Levandowski, downloaded over 14,000 highly confidential and proprietary design files for Waymo’s various hardware systems, including designs of Waymo’s LiDAR and circuit board. To gain access to Waymo’s design server, Mr. Levandowski searched for and installed specialized software onto his company-issued laptop. Once inside, he downloaded 9.7 GB of Waymo’s highly confidential files and trade secrets, including blueprints, design files and testing documentation. Then he connected an external drive to the laptop. Mr. Levandowski then wiped and reformatted the laptop in an attempt to erase forensic fingerprints. Beyond Mr. Levandowki’s actions, we discovered that other former Waymo employees, now at Otto and Uber, downloaded additional highly confidential information pertaining to our custom-built LiDAR including supplier lists, manufacturing details and statements of work with highly technical information.

An accidentally CC’d email leads to a shocking revelation

The most insane thing about this story is that Waymo claims it was alerted to Otto and Uber’s alleged treachery by a mistakenly CC’d email. “Waymo was recently – and apparently inadvertently – copied on an email from one of its LiDAR component vendors. The email attached machine drawings of what purports to be an Uber LiDAR circuit board,” the complaint reads. “This circuit board bears a striking resemblance to Waymo’s own highly confidential and proprietary design and reflects Waymo trade secrets.”

The complaint continues, “As this email shows, Otto and Uber are currently building and deploying (or intending to deploy) LiDAR systems (or system components) using Waymo’s trade secret designs. This email also shows that Otto and Uber’s LiDAR systems infringe multiple LiDAR technology patents awarded to Waymo.”

Waymo claims that Levandowski’s alleged actions were part of a “concerted plan to steal Waymo’s trade secrets and intellectual property,” adding that “months before the mass download of files, Mr. Levandowski told colleagues that he had plans to ‘replicate’ Waymo’s technology at a competitor.”

Waymo is asking the court to block Otto and Uber from using its self-driving technology, and for a return of the allegedly stolen materials.

A spokesperson for Uber said in a statement, “We take the allegations made against Otto and Uber employees seriously and we will review this matter carefully.” Here’s a copy of the complaint.