Square, the payments provider that turns any smartphone into a credit card terminal, is in the process of raising capital at a $6 billion valuation, according to sources familiar with the matter.

The San Francisco-based company, led by Twitter co-founder Jack Dorsey, is aiming to reel in about $200 million, with part of it coming from the Government of Singapore Investment Corporation (GIC), said the sources, who asked not to be identified because the deal hasn't closed.

Asian investors have been piling into the U.S. technology market, backing hot start-ups such as ridesharing service Lyft, video-calling app Tango and texting service Snapchat. It's part of the latest Silicon Valley rush that has lifted dozens of private companies into the billion-dollar club, and pushed some valuations passed $10 billion.

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Square, founded in 2009, was valued at $5 billion earlier this year in a secondary stock sale that let early employees and investors divest some of their shares. Demand from investors exceeded supply, sources familiar with the deal said.

Aaron Zamost, a spokesman at Square, declined to comment. Calls to GIC in Singapore and New York weren't immediately returned.



Square is a hot-button topic in tech land. There's no doubting its popularity. Millions of people, including taxi drivers, food stand owners and yoga instructors, attach the little white dongle to their iPhone or Android device so they can accept credit cards and debit cards, providing a boon to businesses that previously only accepted cash and checks. With increased frequency, the Square Stand (an iPad on a stand) is showing up in coffee shops and restaurants, replacing old clunky registers. The company processes tens of billions of dollars a year in transactions.