In the latest expansion move by a Philadelphia-based law firm, Cozen O'Connor said Thursday that it would merge with a 60-lawyer firm in Chicago, greatly expanding its presence there, and deepening its labor and employment and white-collar defense practices, along with other legal areas.

The merger, effective June 1, will bring the total number of lawyers at Cozen to 635, said the firm's CEO, Michael Heller.

"This gives us a much broader full-service office in Chicago, and allows us to do this with an extremely accomplished group of lawyers with national practices," Heller said of the merger with Meckler Bulger Tilson.

The announcement tracks with a report by the legal-consulting firm Altman Weil of Newtown Square, which found that law-firm mergers this year were off to a blistering pace. The firm said that in the first quarter there were 29 mergers nationally, the second-fastest pace since the company began tracking law-firm mergers in 2007.

The quickened pace of mergers and other activities by law firms, analysts say, suggests that firms are shaking off the effects of the legal downturn of 2008 and 2009.

Two weeks ago, Dechert, another Philadelphia-based firm, announced it was raising salaries for first-year associates in Philadelphia and Princeton by $15,000 to $160,000, matching compensation for starting lawyers in New York, Washington, and other cities.

And last week, Fox Rothschild of Center City said it had recruited a small group of lawyers from Nixon Peabody for its new office in Chicago, its first foray into the Midwest. The office will focus initially on gaming, real estate, and litigation, Fox Rothschild said.

Nationwide, law firms saw an improved profit picture last year, helping to fuel the merger trend.

Cozen has been on a steady growth path for the last few years - its total number of lawyers at the time of the last economic downturn was slightly more than 500. Since then, it has substantially expanded offices in Washington and in New York, where it now has 100 lawyers.

At the same time, Cozen has grown considerably beyond the complex insurance, defense, and subrogation work that formed the core of its business a decade or two ago, to comprise transactional practices, white-collar defense, intellectual property, and other areas.

Heller said the merger with Meckler Bulger was first proposed by a law-firm consultant who had worked for both firms, giving Cozen lawyers a unique window into the business of their potential merger partner. He said it quickly became apparent that Meckler Bulger's insurance, white-collar defense, and other practices fit well with core areas of Cozen's business.

Cozen said that Bruce Meckler, a founder of Meckler Bulger, would serve as vice chair of the combined firm's commercial litigation department and that Joseph Tilson, the current cochair of Meckler Bulger, would serve as cochair of the combined firm's labor and employment department.

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