Earlier Friday, during Cohen's a court proceeding regarding the FBI raid on his offices in NY on Monday, Trump's personal attorney argued the documents and information seized endangered the confidentiality of information that might be unrelated to the FBI's investigation.
A court filing did not detail what Cohen is under investigation for.
In a filing earlier Monday, Cohen's lawyers said investigators "took everything" during raids last week on his residence and office.
In them, they found that Cohen had done "little to no legal work, and that zero emails were exchanged with President Trump".
In her motion, the lawyer, Joanna C. Hendon, asked Judge Wood to give the documents to Mr. Cohen first so that she and the president can look at them and decide if any are protected by attorney-client privilege.
According to reports, Cohen's attorney revealed in court the mystery third client was Sean Hannity. Cohen's attorney said investigators in New York City were referred by Justice Department special counsel Robert Mueller, who is investigating the Russian attack on the 2016 election, from Washington, D.C.
Cohen, meanwhile, immediately holed up in a private room in the courthouse with his lawyers ahead of his appearance. Mueller's office referred the case about his business dealings to NY but hasn't been involved since, the Manhattan prosecutors said. But no matter what it is, the Fox News personality's deranged "crime families" screed after the raid on Cohen's office is starting to make a lot more sense.
Porn star Stormy Daniels, who claims she had an affair with Trump in 2006, is expected to attend. Records related to Cohen's taxi medallion business were also sought. That team, they said, could provide the documents to Trump and other Cohen clients for their own review.
Each search warrant specifically describes how records seized that may fall into attorney-client privilege will be filtered out by a team that's walled off from the federal agents who have conducted the investigation, the prosecutors wrote. He declined to say whether Daniels has met with investigators but told reporters he and his client are "fully cooperating" with the U.S. Attorney's Office.
He complained that Cohen won't disclose the identity of one of them described as a "publicly prominent individual". He states, "As to the one unnamed legal client, we do not believe that Mr. Cohen should be asked to reveal the name or can permissibly do so".
The revelation came after some serious teeth pulling by Judge Kimba Wood, who finally ordered Cohen's lawyers to cough up the name on the spot.
President Donald Trump seems to be consumed with anger and dread following the Federal Bureau of Investigation raid on his longtime attorney Michael Cohen - but two other business associates could deliver even more damning evidence.
The Justice Department is asking for a so-called taint team to vet the material seized in the raids Monday, as is standard process. "All lawyers are deflated and concerned".
Attorney Michael Cohen entered federal court in Manhattan on Monday for the afternoon proceeding. "Attorney client privilege is dead", he exclaimed.
Daniels is expected to appear at Monday's hearing. It is unusual, but not unprecedented, for agents to search a lawyer's records, and there is a policy in place created to shield information covered by the attorney-client privilege.