Marc Mukasey, the high-profile co-chair of Greenberg Traurig's white-collar defense and special investigations practice, has left to start his own trial boutique with other attorneys.

Mukasey, who spoke with ALM on Tuesday, said the boutique expects to add additional partners in the near future from other law firms, including Greenberg partner Robert Frenchman, who worked with Mukasey for the past 10 years.

Mukasey, based in New York, declined to name other possible additions and declined to comment on the firm's official name. He said the firm will announce more details in March.

Mukasey left Greenberg at the end of January 2019. He was at the firm for three years, after joining with Rudolph Giuliani in 2016 from Bracewell. Giuliani left Greenberg last year, amid his ongoing representation of President Donald Trump in special counsel Robert Mueller's investigation.

Mukasey, 51, said he is leaving the Miami-based firm because he wanted to create his own trial firm. Mukasey said he left Greenberg “after three excellent years” and making a lot of friends. “I decided I wanted to start my own law firm, a boutique trial firm,” he said, adding he left on “wonderful terms with Greenberg.”

“My leaving Greenberg had nothing to do with anything other than my desire to start my own law firm,” he said. Mukasey said he doesn't plan on growing the boutique into a large firm. “I intend to keep it lean and mean,” he said.

The boutique will represent corporations and executives in finance, politics, media and sports, among other industries, he said.

Since leaving Greenberg, Mukasey has appeared in court filings for the Trump Foundation and for Jeremy Hutchinson, a nephew of Arkansas Gov. Asa Hutchinson and a former state senator who was charged with spending thousands of dollars in campaign funds on personal expenses,

In the Trump Foundation case, court filings show he has appeared on behalf of the respondents—the foundation, the president and three of his children—in the lawsuit brought by the New York Attorney General's Office. The AG's office alleges that Trump used his charitable organization to fund his 2016 presidential campaign, as well as pay down some of his legal obligations, promote his brand and take care of some personal expenses.

Mukasey declined to comment on his other clients. ”There will be a stable of clients represented by the new firm,” Mukasey said.

Last year Mukasey secured the acquittal of former UBS AG trader Andre Flotron, whom the U.S. attorney in Connecticut had charged with conspiring to commit commodities fraud by manipulating prices of futures contracts for gold, silver and metals.

Mukasey also continues to represent former Louisville basketball coach Rick Pitino, who was not charged in the probe by the Southern District of New York U.S. Attorney's Office over corruption in college basketball recruiting.

Contacted about Mukasey's move, a Greenberg Traurig spokeswoman said, “We wish him well,” adding that the firm's litigation group “remains more than 600 lawyers strong.”