Bronte Media

John Cook, of the Seattle Post Intelligencer, broke the news that Who’s Calling, a call tracking firm that helps advertisers measure return on ad spend, was sold for $55m to Vista Equity Partners.

Vista Equity Partners looks as though they have traditionally invested in enterprise IT and service firms.

Who’s Calling dipped its toe into pay per call (think of the analogy of Double Click moving from ad server to ad network) in 2005 and ended up acquiring the partner they did the trials with earlier this year.

Cook pegs the acquisition price at $55m but doesn’t disclose revenue or profit figures. My guess is that the private equity firm bought it thinking pay per call has the option of being something huge (it does) but that they will find that they are in a business (call tracking) that is becoming increasingly competitive because of the intersection of VoIP putting pricing pressure on products and lowering the barriers to entry. It wont be easy as these firms fight to add value to simple call analytics. That said there are so many opportunities to become the Omniture of calls, or even build a beautiful salesforce.com/CRM integration.