Waymo - a company spun out of Google - filed a lawsuit in February claiming former employee Andrew Levandowski had stolen 14,000 documents relating to LiDAR, a core technology used to guide autonomous vehicles.
Mr Levandowski went on to co-found Otto, a self-driving truck company acquired by Uber for $660m last year.
Waymo requested a judge grant an injunction on the use of the disputed technology, which could take Uber’s self-driving fleet - currently being tested in a few locations in the US - off the roads.
At a hearing earlier this week, Uber sought to convince a judge that an injunction would be unfair.
"Waymo's injunction motion is a misfire,” said Angela Padilla, a lawyer for Uber, said in a statement on Friday.
"There is no evidence that any of the 14,000 files in question ever touched Uber's servers, and Waymo's assertion that our multi-lens LiDAR is the same as their single-lens LiDAR is clearly false.”
Part of Uber’s defence is also an admission that it lags behind its competitors in the autonomous race. It said while it has been developing its own LiDAR tech, it has so far needed to rely on third-party companies to provide the system for its cars.
"If Waymo genuinely thought that Uber was using its secrets, it would not have waited more than five months to seek an injunction,” Ms Padilla added.
"Waymo doesn't meet the high bar for an injunction, which would stifle our independent innovation - probably Waymo's goal in the first place."
Pleading the fifth
Waymo argued that blueprints, mistakenly sent to Waymo via email last December, showed Uber’s plans to use the stolen designs in future.
The company dismissed Uber’s assertion that none of the files were on its servers by pointing out that the firm’s search had not been able to include the computer belonging to the man at the centre of the controversy, Mr Levandowski.
At a recent court hearing, held in private but leaked to the press, Mr Levandowski invoked his Fifth Amendment rights, a constitutional clause that allows US citizens to resist any request to share information that could put them at risk of self-incrimination.
The presiding judge advised that Uber should be firmer with Mr Levandowski in order to get access to the files - such as threatening to fire him if he did not co-operate.
"If you cannot find them in your files there is going to be a preliminary injunction,” Judge William Alsup warned Uber.
"You're not denying it, no one is denying he has the 14,000 files. You keep on your payroll someone who took 14,000 documents and is liable to use them.”
He added: "This is an extraordinary case. I have never seen a record this strong in 42 years. So you are up against it.”
Photo: Uber's fleet is being tested in various locations across the US