SAN FRANCISCO--(BUSINESS WIRE)--Demandbase, a leader in B2B marketing solutions, today announced that David Karnstedt has joined its Board of Directors. Karnstedt has an impressive track record of executive management and advisory roles and expertise in digital advertising with Yahoo!, Adobe and Blue Kai. Recently, he was the President and CEO of Efficient Frontier where he led the company to a successful acquisition by Adobe for more than $400 million. “Demandbase is the first company I have s