A federal judge overseeing thousands of lawsuits over combat earplugs questioned 3M’s actions prior to its subsidiary’s bankruptcy filing last month, including what she described as potential fraud on the court.

At a Thursday hearing, U.S. District Judge M. Casey Rodgers, in Pensacola, Florida, continued to focus on an indemnity agreement 3M reached on July 25 to transfer liability to its subsidiary, Aearo Technologies, which, one day later, filed for bankruptcy.