RealNetworks' former CEO Robert Kimball

After a little more than a year at the helm, Robert Kimball is stepping down as RealNetworks' chief executive.

"After 12 amazing years at Real, it is time for me to find new challenges and opportunities," Kimball said in a statement. "I took on this role to lead a restructuring and transformation of RealNetworks into a more lean, efficient, and effective business and we have completed that phase of RealNetworks' transformation. Over the past year we have simplified our business, removed more than $70 million in annualized operating expenses and created an entirely new, award-winning product called Unifi."

Mike Lunsford, Real's executive vice president, will serve as interim chief executive officer while the board searches for Kimball's replacement. Lunsford worked at EarthLink from 1999 to 2007, including a stint as the Internet service provider's interim chief executive.

Kimball took over as president and interim CEO for the media software company in January 2010 when founder Rob Glaser resigned after 16 years as chief executive. Kimball, who was previously the company's general counsel, was officially named Real's CEO in July 2010.

Glaser, who still serves as Real's chairman, praised Kimball's tenure running the Seattle-based company.

"We deeply appreciate Bob's strong leadership through a difficult transformation," Glaser said. "As CEO, he accomplished a lot in a short time. He has established a strong foundation upon which the company can build in the years to come. "

Shares of Real closed up 3 cents today to $3.94, or 0.77 percent. The company's stock price has declined 18 percent in the past 12 months.