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March 26 (Reuters) - Cloud-based payroll processor TriNet Group Inc TNET.N said it priced its initial public offering at $16 per share, valuing the company at about $1.09 billion.

Backed by private equity firm General Atlantic LLC, TriNet's expected offering of 15 million shares would raise about $240 million at that price, which is at the mid-point of its planned $15-$17 price range. ID:nPn1b92ZR

The stake held by General Atlantic, the company's top shareholder, will drop to 56 percent after the offering from 71.4 percent.

TriNet's shares will start trading on the New York Stock Exchange on Thursday under the symbol "TNET."

Small and medium-sized businesses outsource payroll, employee-benefit and other human resources functions to San Leandro, California-based TriNet, which offers a cloud-based technology platform. The company served more than 8,900 clients in 47 states, the District of Columbia and Canada as of Dec. 31, it said in a filing.

The company, which counts Automatic Data Processing Inc

ADP.O , Insperity Inc NSP.N and Paychex Inc PAYX.O among its main competitors, said net proceeds from the offering would be used to repay outstanding debt.

TriNet has been highly acquisitive, buying premium HR services company Ambrose Employer Group LLC, technology firm App7 Inc and insurance and risk-management service provider Gevity HR Inc.

Shares of online payroll processor Paylocity Holding Corp

PCTY.O soared in their debut last week as investors kept their faith on cloud-based enterprise software companies.

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TriNet's net income fell to $13.15 million in 2013, from $31.83 million a year earlier. Revenue rose, however, by 61 percent to $1.64 billion last year.

JP Morgan, Morgan Stanley and Deutsche Bank Securities are among the lead underwriters for the offering.

(Reporting by Avik Das and Rohit T.K. in Bangalore. Editing by Andre Grenon and Steve Orlofsky)

((avik.das@thomsonreuters.com)(within U.S. +1 646 223 8780)(outside U.S. +91 80 6749 1130)(Reuters Messaging: avik.das.thomsonreuters.com@reuters.net))

Keywords: TRINET GROUP IPO