A U.S. judge on Wednesday formally approved a request by prosecutors to dismiss all remaining charges against ex-Credit Suisse Group banker Frank Quattrone.
The decision came four years after Quattrone was accused of obstructing justice and 17 months after his conviction for the crime was reversed.
Last August, the government agreed to drop its case if Quattrone, 51, didn't break the law for a year.
The dismissal means Quattrone, head of Credit Suisse First Boston's technology banking group from 1998 to 2003, is free to return to the financial industry he left when he was indicted.
"The [government's] criminal casebook is now closed," said Jacob Frenkel, a former federal prosecutor now in private practice in Rockville, Md. "With the one-year clock having run, there is nothing left hanging over Mr. Quattrone's head."
U.S. District Judge George Daniels signed the dismissal.
Quattrone, who federal regulators said earned more than $200 million from August 1998 to the end of 2001, is currently chairman of the Tech Museum of Innovation in San Jose.
The Quattrone case grew out of a probe of whether banks rigged initial public offerings by demanding kickbacks for access to shares. The IPO investigation was one of several federal civil and criminal probes of corporate malfeasance after the 2001 collapse of Enron Corp.
Quattrone was accused in April 2003 of hindering the government's investigation of Zurich-based Credit Suisse, Switzerland's second-largest bank, by endorsing a subordinate's e-mail that advised employees to "clean up" their files.
Prosecutors said he sent the message, suggesting that subordinates destroy records, after learning that a grand jury was probing how Credit Suisse doled out IPO shares.
Quattrone faced two trials. The first ended in a hung jury in 2003. The second resulted in a conviction for obstruction of justice and witness tampering in 2004. He was sentenced to 18 months in prison before an appeals court last year reversed the conviction.
Prosecutors decided not to retry him and agreed last August to drop the case after a year.