Social score startup Klout has been acquired by Lithium Technologies, a provider of social customer experience solutions for the enterprise, in a deal valued at nearly $200 million, Fortune has learned. According to two sources familiar with the matter, the deal is a mix of cash and Lithium private stock. (Lithium is gearing up for an IPO, which could happen as early as later this year.) Klout and Lithium are expected to announce the acquisition Thursday morning in a joint press conference. Technology news site Re/Code reported last month that a deal was signed but not closed. A spokesperson for Klout and Lithium declined to comment. Klout's history has been an interesting one. The startup was co-founded by CEO Joe Fernandez and Binh Tran in 2008 as a way to measure influence on the growing social web.