Search giant Google has accused Uber of stealing technology used to develop self-driving cars in a lawsuit that could cost the taxi firm US$1.5billion.
Google's sister self-driving car technology company Waymo is claiming Otto employees – Uber's autonomous car start-up – poached large amounts of information from them.
The Sun reported that the "calculated theft" only came to light after Waymo accidentally received an email that depicted an Uber circuit board that was similar to its own design.
The newspaper reported that court documents said: "Fair competition spurs new technical innovation, but what has happened here is not fair competition."
"Otto and Uber have taken Waymo's intellectual property so that they could avoid incurring the risk, time, and expense of independently developing their own technology."
Waymo claims that Uber stands to make as much as US$500million from the alleged theft, and is seeking compensation worth three times that figure.
Waymo is now asking that a San Francisco court award it "significant damages", which includes the "trebling" of the US$500million figure by what it is calling Uber's "unlawful conduct".
According to The Sun, it was alleged that he downloaded more than 14,000 confidential documents prior to leaving the search giant.
Waymo said in a blog post on its website: "Misappropriating this technology is akin to stealing a secret recipe from a beverage company.
"We believe these actions were part of a concerted plan to steal Waymo's trade secrets and intellectual property."