BREAKING NEWS: RealNetworks founder Rob Glaser has stepped down as CEO, the company just announced. No specific reason was given. He'll remain the company's chairman.

"After nearly 16 years, I’ve decided it’s time for me to step away from day-to-day operations,” Glaser said in a statement released by the company. “I’m grateful to all of our stakeholders – customers, partners, shareholders, and most of all, employees – for the support and commitment they’ve given to RealNetworks. I remain committed to the company and look forward to continuing to serve in my capacity as board chairman.”

Robert Kimball, RealNetworks' general counsel, has been named president and acting chief executive officer.

The Wall Street Journal's AllThingsD technology blog, citing anonymous sources, reports that Glaser was "forced out" -- that his resignation was "instigated by his own board but that Glaser eventually cooperated with the decision."

Asked about the report, RealNetworks spokesman Bill Hankes didn't address it specifically, saying simply that Glaser "decided to step down because the timing was right for him."

On Monday night, the day before his resignation became official, Glaser posted on Twitter: "Today wasn't such a great day, which made regular dinner with the kids feel even more magical than usual. I am a very lucky guy."

Glaser founded RealNetworks in 1994 and built the company into an early pioneer in streaming media on the Internet, starting with the introduction of RealAudio in 1995. After winning a $761 million antitrust settlement in 2005 from Microsoft, Glaser's former employer, the company has suffered a series of high-profile legal setbacks in its battle with Hollywood studios over its RealDVD product.

Glaser resigned Tuesday, and the company’s board appointed Kimball as president and acting CEO the same day, according to a RealNetworks filing with the Securities and Exchange Commission. Kimball was also added to the board, expanding RealNetworks’ board to seven members.

Kimball, 46, joined RealNetworks in 1999 and has served in a variety of executive posts at the company. He’s held the title of general counsel since 2003.

The RealNetworks board plans to start searching for a new CEO, and Kimball will be among the candidates for the permanent position, spokesman Hankes said. Kimball's appointment as president of the company is permanent, as is his position on the board, Hankes said.

RealNetworks has suffered financially in recent years, recording substantial charges for impairment of goodwill, but the company returned to a quarterly profit, just barely, in the third quarter.

Glaser still has a significant financial interest in the company, owning more than 38 percent of its common stock, according to a RealNetworks filing in November.

Over the past year, the company has sought to position itself to take advantage of new technological platforms -- building connections from its RealPlayer software to Twitter and Facebook, and developing Rhapsody music apps for the iPhone and Google Android devices.

This afternoon, Glaser posted on Facebook the message that he sent to the company's employees announcing his decision.

"While there's never an ideal time to make a change like this, this is as good a time as any," the message reads, in part. "We've weathered the brunt of the Great Recession and have done what we said we wanted to do, which was to keep our core solid while also building for the future. We've also undertaken an extremely rigorous strategy review and have a very exciting road map for the future that you'll hear about in the days and weeks ahead. And the start of a new decade is a good time, poetically, to pass the baton."

RealNetworks may have hinted at one element of that "strategy review" in November. The company disclosed in an SEC filing that it had been talking to Viacom's MTV Networks about restructuring their Rhapsody joint venture -- aiming to possibly end RealNetworks' majority control of the music service.

Glaser, an outspoken supporter of the Obama administration, is expected to focus on his political and philanthropic interests, in addition to his family, spokesman Hankes said. He said Glaser was on a flight to Washington, D.C., on Wednesday afternoon and was unavailable for an interview.

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Eric Engleman contributed to this report.

Post updated at 2:24 p.m.