Karnstedt was CEO at Efficient Frontier for almost three years, from 2009 to its sale in 2012, prior to which he was an executive in residence at Redpoint Ventures. Before that he held numerous sales leadership roles at Yahoo, including SVP of North American sales. His search industry experience dates back to Overture and AltaVista.
Karnstedt, who did not respond to an interview request, still has a hand in several digital marketing firms. Since December 2012 he has sat on the board of Quantifind, a predictive analytics player funded by Redpoint Ventures and Andreessen Horowitz. Quantifind is based in Menlo Park and co-founded by Stanford grads John Stockton and Ari Tuchman.