By Mike Scarcella

WASHINGTON, May 11 (Reuters) - National U.S. plaintiffs law firm Keller Postman has appealed a judge’s decision on Friday sanctioning it and one of its founders for allegedly misusing confidential information in lawsuits alleging the pain-reliever acetaminophen caused autism in children.

The firm appealed to the 2nd U.S. Circuit Court of Appeals on Saturday, a day after U.S. District Judge Denise Cote in Manhattan ruled that Keller Postman and co-founder Ashley Keller breached court orders by using confidential documents in federal acetaminophen litigation to back their legal arguments in related state court cases in Florida and Texas.

Keller Postman has argued that it did not violate confidentiality orders, and has said no confidential information was publicly disclosed.

"We strongly disagree with the Court's decision, and will seek reversal as expeditiously as possible in the Second Circuit," Keller Postman said in a statement on Monday, adding that the firm will "obey all court orders while vigorously advocating" for its clients.

Tylenol maker Kenvue KVUE.N, a defendant in the litigation, and a lawyer for the company did not immediately respond to requests for comment.

Keller Postman has served as co‑lead counsel for plaintiffs in federal litigation in Manhattan since 2022 against Kenvue and retailers that sold store-brand acetaminophen. Kenvue has said repeatedly that Tylenol is safe.

Cote on Friday ruled that Keller Postman in a related lawsuit in Florida state court improperly quoted from 11 pages of emails that had been designated as confidential in the federal case in Manhattan. The firm had told the state court that the material was confidential and should be sealed, but the court declined to seal the submission.

The judge said Keller Postman in the related Texas lawsuit willfully used material that was deemed confidential in the federal case. Keller Postman is working as co-counsel with the Texas attorney general’s office in the Texas case.

Cote rejected arguments by Keller Postman that filing materials under seal or in redacted form in Texas complied with an order in the federal litigation restricting disclosure of information.

As a sanction, Keller Postman was ordered to pay legal fees to Kenvue and to show Cote’s order to every lawyer working on the federal litigation and related lawsuits.

The case is In re Acetaminophen - ASD-ADHD Products Liability Litigation, U.S. District Court, Southern District of New York, No. 1:22-md-03043-DLC.

For plaintiffs: Ashley Keller of Keller Postman

For Kenvue: Jessica Brennan of Barnes & Thornburg

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