(Reuters) - Proskauer Rose’s former chief operating officer asked a federal judge on Wednesday to reject claims that he stole the law firm's trade secrets, accusing Proskauer of filing a "vindictive" and "baseless" lawsuit to deter others from quitting the firm.

New York-based Proskauer fired its COO Jonathan O’Brien last month and sued him in Manhattan federal court the same day, claiming he tricked firm employees into letting him copy sensitive client and compensation data before giving notice on Dec. 20 that he was quitting. Proskauer asked the court for an injunction blocking him from sharing its data or taking a planned new job.

O'Brien countered Wednesday that he only downloaded internal documents so that he could work during a two-week vacation. He said he never intended to use any of that information at a new job at competitor law firm Paul Hastings, which he said rescinded its offer anyway based on Proskauer's allegations.

“Mr. O’Brien did precisely what any COO traveling abroad at year end would have done; he took steps to ensure that he had the information he would need to do his job, and nothing more,” his lawyers told the court .

The real motivation behind Proskauer's lawsuit is to intimidate and dissuade other employees from leaving the firm after a spate of recent partner and business-side departures, O'Brien alleged, accusing the firm of "Machiavellian management."

Proskauer said in a statement Thursday that it did not take the decision to sue O'Brien lightly.

“Mr. O’Brien’s narrative ignores the evidence which will demonstrate that his statements are false and that he engaged in a malicious conspiracy to steal trade secrets," the firm said.

O'Brien told the court he is considering filing counterclaims "against both Proskauer and the individuals at Proskauer in their personal capacity who are driving this vindictive litigation," which he said has left him "unemployed for the foreseeable future."

“Proskauer has improperly used the judicial system as a sledgehammer to destroy Mr. O’Brien’s career and reputation,” he said.

A Paul Hastings spokesman said earlier this week that O'Brien is not joining the firm but declined to comment further, citing a policy not to discuss "any firms' personnel matters."

The case is Proskauer Rose LLP v. O’Brien, S.D.N.Y., No. 1:22-cv-10918

For plaintiff: Michael Mervis of Proskauer Rose

For Defendant: Russell Beck of Beck Reed Riden; Russell Yankwitt of Yankwitt LLP

Read more:

Law firm Proskauer sues ex-COO, claiming data theft

Former Proskauer exec facing theft lawsuit planned to join Paul Hastings

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