Uber will be allowed to depose Alphabet CEO Larry Page as well as David Drummond, the company’s chief legal officer and senior vice president of corporate development, according to court documents filed Friday. The depositions were requested by Uber, which is being sued for alleged patent infringement and stealing trade secrets by Waymo, the Google self-driving project that spun out to become a business under Alphabet.

Uber views these depositions as critical information to determining Alphabet’s motivation behind the suit and whether it was simply a tactic to delay the development and deployment of its self-driving vehicle technology. The ride-sharing company first requested to depose Page during a discovery hearing in April.

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The court ruling signals an escalation between two companies that were once on friendlier and much closer terms. Google’s venture arm invested in Uber in 2013.

Drummond, who oversaw Google Ventures’ investment in Uber, once held a seat on Uber’s board, but stepped down in August over rising conflicts of interest between the two companies.

The court placed has some limitations on the depositions. Both depositions are limited to four hours. The court also ruled that Uber does not need to take Drummond’s deposition regarding why Google (GOOG) did not partner with Uber because “that is a topic on which they are deposing Mr. Page.” The ride-hailing company wants to ask Drummond about conversations he had with Travis Kalanick, who was CEO of Uber until late June, and his knowledge of the Uber/Otto deal, according to the filing.

Waymo has insisted that depositions are not appropriate. But the court agreed with Uber’s argument that Page has “first-hand non-repetitive knowledge of relevant facts.”