Squire Sanders has finalised its long-awaited merger with Washington firm Patton Boggs, with the combined outfit to go live on 1 June.

The new firm will be known as Squire Patton Boggs.

Two weeks ago, Legal Week reported that a tie-up between the two firms was imminent, after Patton Boggs turned down a rival offer from Dentons.

A source involved in the discussions said that Dentons' offer of a merger with Patton Boggs – described by the former firm's chief executive Elliott Portnoy in April as a "serious overture" – had yielded no further developments or discussions.

Squire Sanders briefly suspended voting last Wednesday, after a former client of Patton Boggs sought to block a settlement struck earlier this month between the firm and oil giant Chevron.

Squire Sanders management is understood to have delayed the vote to "do right by the partnership and consider the risks", one person close to the situation said. Management decided to press ahead with the vote on Thursday.

The merged firm will have approximately 1,600 lawyers across 45 offices in 21 countries. There will be combined offices in Washington, New York and Riyadh. The tie-up places the firm among the top 25 firms globally in terms of lawyer headcount.

Jim Maiwurm, chair and global CEO of Squire Sanders said: "Today marks an important day in the history of our firm. Patton Boggs is the premier public policy firm in the world, and this combination establishes us as the 'go-to' firm for public policy work.

"We also gain a leading position in the Middle East and several new locations in the United States, while deepening our bench in a number of important practices areas, all of which strengthen our service platform."

Thomas Hale Boggs, chairman of Patton Boggs, added: "When Patton Boggs was founded over 50 years ago we set out to create an innovative firm that brings legal expertise and lobbying know-how to government and business leaders around the world. That firm evolved into an industry game-changer.

"Through our combination with Squire Sanders we are doing it again, by bringing together our rich experience with one of the world's most expansive practice and geographic footprints."

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