Rob Glaser, the company's founder and chairman, has returned to the CEO job to fill in on an interim basis, RealNetworks said.

Nielsen is not leaving to take a position elsewhere, the company said in a Tuesday.

RealNetworks has struggled financially in recent months. The company reported a net loss of US$17 million in the first quarter of 2012, following a loss for the full year in . In January, it sold $120 million in video software and patents to chip maker Intel.

"I come back to RealNetworks with a sense of great urgency to set the company on a long-term path to success," Glaser said in the statement.

Glaser founded RealNetworks in 1994. Prior to that he had been vice president of multimedia and consumer systems at Microsoft.