Lehman Bros. Holdings Inc., which last month filed the largest bankruptcy in history, is the subject of three federal criminal probes and at least 12 subpoenas, according to a lawyer for the failed bank.

The investigations were launched by U.S. attorneys in Brooklyn and Manhattan, as well as in Newark, N.J., Harvey Miller, the lead Lehman bankruptcy lawyer, said in New York federal court this week.

They are focusing on Lehman's role in the $330 billion auction-rate securities market and possible crimes associated with its $6 billion June issuance of stock, according to a person familiar with the case.

"It's clear they have given it some urgency and priority," said Robert Plotkin, a former Justice Department lawyer, now a white-collar criminal defense lawyer at McGuireWoods, in Richmond, Va. "Given the notoriety and the headlines, this would be one of the ones that would be on a faster track."

The demise of Lehman, which sought court protection Sept. 15, accelerated a global credit crisis that has wiped out $30 trillion of equity value in the last year. The United States has begun investigations of mortgage lending, securitization, and failed banks, including New York-based Lehman.