Google gives Apple a 36 percent cut of all search ad revenue that comes from Safari, according to University of Chicago professor Kevin Murphy. Google had fought to keep the number confidential, but Bloomberg reports that Murphy shared the figure while testifying in Google’s defense today at the Google antitrust trial.

Google has long paid to be the default search engine in Safari and other browsers like Firefox, spending $26.3 billion in 2021 alone for the privilege. $18 billion of that went to Apple, but the specifics of where the number came from remained secret until now. Google has been trying to keep such details under wraps as the trial goes on, but bits and pieces have seeped out anyway. According to Bloomberg, Google lawyer John Schmidtlein “visibly cringed when Murphy said the number.” Google declined to comment in an email to The Verge; Apple did not immediately respond to a request for comment.

Apple’s Eddy Cue defended the deal in September, saying Apple actually wanted a bigger cut of the money Google makes from Safari traffic, but the companies settled on the lower number Murphy revealed today. While specific numbers were discussed that day, they were only talked about in closed sessions, away from the ears of press.

Update November 13th, 4:38PM ET: Updated to reflect that Google had no comment.