Top 50 US law firm Perkins Coie has hired partners from Vinson & Elkins and Wilson Sonsini Goodrich & Rosati to open an office in Austin, Texas.

The move comes in the same week that Shearman & Sterling unveiled its third Texas office, in Dallas, after hiring three corporate partners from Jones Day.

The hiring spree underlines the sustained interest by ‘big law’ US firms in the Texas triangle - a region of more than 20 million people encompassed by Dallas, Austin, Houston and San Antonio that was last year identified by CityLab as one of 29 megaregions that power the global economy.

According to Law.com, nearly half the Am Law 200 law firms have at least one office in Texas.

Perkins Coie’s Austin office will be its second in Texas: its Dallas office opened for business ten years ago and now houses 30 lawyers.

The practice will target clients in the so-called ‘Silicon Hills’ cluster of technology companies and will be led by three senior lateral hires who are joining as partners and specialise in tech law.

Arriving from Vinson are trial and appellate lawyer Craig Tyler, who was a partner, and corporate specialist Andy Smetana, who was a counsel; while trial lawyer Jose Villarreal is arriving from Wilson Sonsini.

“We see significant strategic opportunities in Texas as Austin and Dallas continue to grow as business centres for startups, medium-sized companies, and large, global corporations,” said Perkins Coie managing partner Bill Malley.

The Austin office is Seattle-based Perkins Coie’s 20th overall and its 17th in the US. Its international offices are all Asia-based: in Beijing, Shanghai and Taipei.

Meanwhile, Shearman, which confirmed it was opening in Dallas last week, has unveiled the six-partner team that will be leading the practice.

They include three corporate partners secured from Jones Day: Scott Cohen, Robert Cardone and Alain Dermarkar.