Australian duo Gilbert & Tobin (G&T) and Allens Arthur Robinson have bagged high-profile lead roles on the $17.5bn (£8.99bn) merger between Westpac Banking Co and domestic rival St George Bank, writes The American Lawyer.

Westpac – Australia's fourth-largest bank – turned to G&T, while St George – the country's fifth-largest lender – instructed Allens Arthur.

M&A partners John Williamson-Noble, Gary Lawler and Jason Lambeth led the team for G&T, which was founded in Sydney in 1988 and has since grown into a 200-lawyer full-service outfit with a reputation for large-scale commercial transactions. Competition partner Gina Cass-Gottlieb also took a major role.

A 15-lawyer team for Allens Arthur – one of Australia's so-called 'big six' law firms – was led by M&A and capital markets co-head Ewen Crouch. Assisting Crouch were M&A partners Victoria Poole and Jeremy Low; competition partners Fiona Crosbie and Jacqueline Downes; finance partners Ian Wallace and Mark Wormell; tax partner Tony Sheehan; and litigation partners Michael Ball and Richard Harris.

The deal would create Australia's largest bank if successful but must first clear some major regulatory hurdles in Australian competition law.

One US lawyer familiar with the market Down Under commented: "They have a four-pillar policy in Australia, which means that each of the four top banks are not permitted to combine with any of the other top four banks. Both Westpac and St. George are significant New South Wales banks so there may be some competition issues."

The antitrust aspects of the deal are of particular importance because the Australian Competition & Consumer Commission and Wayne Swan, the nation's treasurer, must approve any final acquisition.

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