A computer expert claims in a lawsuit that Minneapolis law firm Leonard, Street and Deinard owes him $775,000 for storing digital evidence in a case involving the city’s two largest newspapers.

Mark Lanterman of Computer Forensic Services said he stored 62 terabytes of Star Tribune data, costing $155,000 a month, for five or six months before he deleted it, the Star Tribune reports. He claims the law firm still owes him $775,000 in unpaid bills.

The law firm’s reply to the suit says Lanterman has already been paid "handsomely" for every invoice he submitted on time, for a total of $854,000, the story says. The last invoice came in too late for the firm to bill the Star Tribune, ordered to pay expenses in the case, the court document said. The firm also says it didn’t have a signed contract with Lanterman.