The founder of MySpace.com parent Intermix Media Thursday said he is seeking a federal investigation of the sale of Intermix to News Corp. (NWS) last year, claiming the deal defrauded shareholders by undervaluing the Internet's most popular networking site.

Brad Greenspan, Intermix founder, has been an outspoken opponent of the deal and in February sued the News Corp. unit and venture capital firm VantagePoint Venture Partners for breach of fiduciary duty.

On Thursday, Greenspan accused former Intermix Chief Executive Richard Rosenblatt of hiding revenue growth data at MySpace from shareholders to present a distorted financial picture and execute a deal quickly.

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Greenspan's claim contends MySpace could now be worth more than $20 billion.

"He knew it was worth billions of dollars, he was able to pass it off to News Corp. to get a sweetheart deal for himself," Greenspan said in a telephone interview. "The shareholders paid a massive price here."

His report can be found at http://www.freemyspace.com.

Citing internal company reports he has now uncovered, Greenspan said MySpace revenue grew 1289 percent on an annualized basis from Dec. 2003 through June 2005.

Most shareholders were only privy to information on growth in other units, which, including MySpace, logged a revenue growth rate of a much lower 52 percent over the same period.

Reuters was not able to independently verify the new revenue figures.

News Corp., which disputed Greenspan's account, purchased Intermix last year for $580 million.

Rosenblatt was not immediately reachable for comment.

The media company controlled by Rupert Murdoch has since ridden a wave of investor and analyst approval for capturing MySpace, now one of the Web's fastest growing properties.

In late September, RBC Capital analyst Jordan Rohan said MySpace could be worth about $15 billion within three years.

Greenspan bid against News Corp. to buy the rest of Intermix he did not own last year, but lost after Intermix's board voted against his deal.

"It's unfortunate that Mr. Greenspan continues to issue press releases complaining about a deal that many industry experts initially believed was a risk for News Corp. to take," a spokeswoman for News Corp.'s Fox Interactive Media said.

"We've strategically built this business since the acquisition and are just now beginning to realize real financial value," the spokeswoman said. "This is simply a case of sour grapes making for loud complaints."

Greenspan left Intermix in 2003 amid an informal U.S. Securities and Exchange Commission inquiry and accounting restatements.

He retained an approximate 11 percent share of the company, which last year settled a lawsuit filed by New York Attorney General Eliot Spitzer charging the company with illegally downloading intrusive adware and spyware software into millions of computers.

Greenspan was ordered to pay $750,000 in fines under the settlement with Spitzer.

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