Marriott has turned to Baker & Hostetler to represent the hotel chain in a growing number of class actions brought over its massive data breach.

On Tuesday, Baker & Hostetler's Daniel Warren, a partner in Cleveland, filed a court appearance to represent Marriott before the U.S. Judicial Panel on Multidistrict Litigation, which is hearing arguments on Jan. 31 in Miami over whether to coordinate the cases spurred by the event. Lawyers have filed about 50 class actions since the breach, which compromised personal information such as the passport numbers of 500 million guests of Marriott's Starwood properties.

Marriott so far has not responded to allegations in the lawsuits that its negligence caused the breach.

Warren also has appeared in individual cases, along with a team from Baker & Hostetler's Washington, D.C., office that includes Gilbert Keteltas, head of the firm's commercial litigation practice, and Mark Bailen, Danyll Fox and Carey Busen. Other partners, such as Lisa Ghannoum in Cleveland, Curt Hineline in Seattle, and Teresa Chow in Los Angeles, have appeared in individual cases for Marriott.

A representative for Baker & Hostetler did not respond to a request for comment. Warren, Keteltas, Bailen, Fox and Busen also did not respond.

According to Baker & Hostetler's website, Warren, who also works in Chicago, has considerable experience with data breach defense, including getting many claims against Community Health Systems dismissed in a multidistrict litigation over a 2014 breach. In April, Warren convinced the U.S. Court of Appeals for the Seventh Circuit to uphold dismissal of a data breach case brought by several banks against Midwestern grocery store chain Schnucks.