A jury in a trade-secrets lawsuit will get its first earful Monday as opening statements begin in a bitter legal battle between Waymo and Uber Technologies Inc that has captivated Silicon Valley and could help determine who emerges in the forefront of the fast-growing field of autonomous cars.


Testimony in San Francisco federal court is expected to last two weeks before the decision in the lawsuit, filed by Alphabet Inc’s self-driving car unit Waymo nearly a year ago, goes to the 10-person jury. It promises to be a showdown between the two technology companies over allegations by Waymo that one of its former engineers took trade secrets just before quitting and going to work at ride-hailing firm Uber.


The case hinges on whether Uber used apparent trade secrets, a total of eight according to court filings, to advance its autonomous vehicle program.


Waymo said engineer Anthony Levandowski downloaded more than 14,000 confidential files in December 2015 containing designs for autonomous vehicles before he went on to lead Uber’s self-driving car unit in 2016.


The jury will have to decide whether these were indeed trade secrets and not common knowledge, and whether Uber improperly acquired them, used them and benefited from them.


Uber has said while Levandowski downloaded the files, the data never made their way into its own self-driving car designs.


Levandowski, regarded as a visionary in autonomous technology, is not a defendant in the case but is on Waymo’s witness list.


Levandowski was fired from Uber in May 2017 because the company said he refused to cooperate with Uber in the Waymo lawsuit and did not hand over information requested of him in the case.


Waymo and Uber are part of a crowded and hotly competitive field of automakers and technology companies aiming to build fleets of self-driving cars that could transform urban transportation systems.


Waymo has estimated damages in the case at about $1.9 billion. Uber rejects the financial damages claim. Still, the lawsuit has hobbled Uber’s self-driving car program, with Uber attorney Bill Carmody telling the court last week that the case “is the biggest in the history of Uber.”


Waymo intends to call Waymo Chief Executive Officer John Krafcik as it first witness, court documents show. Uber has co-founder and former CEO Travis Kalanick at the top of its witness list.


There are a total of 99 potential witnesses between the two companies, according to court documents, including Google co-founders Larry Page and Sergey Brin, Benchmark venture capitalist and Uber investor Bill Gurley and Alphabet executive David Drummond.


The U.S. Department of Justice is conducting a separate criminal investigation into what transpired, according to court filings.