U.S. Magistrate Judge Jacqueline Scott Corley of the Northern District of California has formally thrown a wrench into Uber’s plan to tell jurors that Anthony Levandowski may have had an innocent reason for downloading Google’s autonomous car files.

Corley ruled Monday that a March 29 conversation on the subject between then-CEO Travis Kalanick; Levandowski, then the head of Uber’s driverless car division, and Uber litigation chief Angela Padilla is “classic attorney-privileged communications.” Corley’s ruling, if adopted by U.S. District Judge William Alsup, appears to head off a nascent defense to Google’s claims of trade secret theft.