SAN FRANCISCO — As if the legal feud between driverless car rivals Waymo and Uber didn’t already involve enough lawyers, Kirkland & Ellis is now wading into the fray.

Robert Ellis, a litigation partner in Kirkland’s Chicago office, entered an appearance Tuesday afternoon on behalf of Stroz Friedberg LLC. The company, which bills itself as a “specialized risk management firm,” produced a due diligence report that has taken center stage in Waymo’s trade secrets theft case against Uber.