Proskauer Rose is grabbing three attorneys from Mayer Brown to launch its new office in Chicago, opening the doors with a group of litigators in the insurance arena.

The law firm’s Chicago hires will include Mayer Brown partners Steven R. Gilford, Marc E. Rosenthal and Paul L. Langer, according to sources familiar with the firm’s plan. All of the lawyers have focused their work on representing corporate policyholder clients as opposed to insurance companies.