Group 1's dealerships in the U.K. don't use CDK's dealers' systems and are not impacted by the incident. In regulatory filings, Lithia Motors and AutoNation disclosed that last week's incident at CDK had disrupted their operations as well. Lithia said it activated cyber incident response procedures, which included "severing business service connections between the company's systems and CDK's." AutoNation said it also took steps to protect its systems and data — adding that all of its locations remain open "albeit with lower productivity," as many are served manually or through alternative processes.