Private equity firm Blackstone Group LP, along with Pactera's CEO and other managers, have offered to take Pactera private in a deal that values the Chinese technology consulting and outsourcing firm at $680.4 million. Shares rose 31 percent Monday. Through Friday's close, before news of the offer, Pactera's stock had lost about two-thirds of its value over the past year. Blackstone and the group of Pactera leaders are offering $7.50 for each U.S.-traded share of the company that they don't already hold. That's 43 percent higher than Friday's close of $5.26 on the Nasdaq stock market and puts the value of the company at $680.4 million, based on Pactera's the estimated 90.7 million shares outstanding. The group of potential buyers working with Blackstone includes Pactera's non-executive chairman, Chris Chen, its CEO, Tiak Koon Loh, and three of its executive committee members. Pactera said that its board will likely form a special committee of independent directors to review the proposal. It is one of several recent buyouts efforts by private equity firms of U.S.-listed Chinese companies. Citic Capital Partners said last week that it, along with one of the company's co-founders, would take technology services firm AsiaInfo-Linkage Inc. private in a roughly $890 million deal. Focus Media Holdings Ltd. shareholders agreed in April to a deal to sell the Chinese advertising company to private equity firm Carlyle Group and a handful of Chinese investors for $3.7 billion. Shares of Pactera jumped $1.61 to $6.87 by early afternoon.