A former Bingham McCutchen partner has slapped his former lawyers at Cotchett, Pitre & McCarthy with a multimillion-dollar professional negligence lawsuit, claiming they mishandled an arbitration where he was seeking millions in unpaid compensation guarantees from his old law firm.

In a complaint filed in San Francisco Superior Court on May 24, lawyers for former Bingham partner Michael DiSanto claims he had a written agreement with the firm that guaranteed him $2.5 million in annual compensation from when he joined in March 2013 through 2015, and at least $1.5 million in 2016, including salary and bonus.

According to the complaint, DiSanto hired the Cotchett firm and Philip Gregory, then a partner at Cotchett, shortly after DiSanto says he was terminated without cause in November 2014. Gregory was hired to pursue claims in arbitration against Bingham for failure to make good on the compensation agreement. DiSanto claims Gregory and the firm negligently mishandled his case and lost counterclaims that resulted in him having to hand over stock units he had been awarded by his prior employer, Maker Studios, where he previously served as general counsel.