Billionaire hedge fund manager Steven A. Cohen may see the last of his outside investors ask for their money back by midnight on Friday.

After the U.S. government charged Cohen's $14 billion SAC Capital Advisors with securities and wire fraud last month, the bulk of outside clients who are still in the fund are likely to file their redemption notices now, three people familiar with the fund said.

"Most of the outside money is already gone and what little is left will probably decide it's time to go now," said one former SAC investor who asked to remain anonymous because he is still in touch with the manager.

A SAC spokesman declined to comment.

Some of the money that might be pulled out now could include the $500 million that was invested in the hedge fund's reinsurance unit SAC Re which was in turn invested in the hedge fund.

Outside investors had already put in redemptions for $1.68 billion in February and an estimated $3 billion at the June deadline. The current deadline is at midnight on Friday.

Aug. 16 marks a regular redemption date for SAC and many other hedge funds, giving wealthy investors, endowments and funds of funds one of only a handful of chances this year to ask for their money back.

The deadline however is not expected to affect SAC's operations significantly because some $9 billion of the fund's assets belong to Cohen and his top managers and is expected to stay in the fund.

Outside investors, including Blackstone Group, Morgan Stanley, Magnitude Capital and Ironwood Capital, who have requested money back already this year will have it returned to them by year's end.

The departure of outside capital gave rise to speculation that SAC might turn itself into a family office, consider making layoffs or scale down the size of its operations. The firm has told employees this will not be the case.

SAC President Tom Conheeney told employees in a recent e-mail that the firm will have as much to invest at the end of this year as it did at the end of 2009.

And outside investors will still be able to put money into the Stamford, Connecticut-based fund, former investors have been told even though several said it is highly unlikely that SAC will be able to attract fresh outside capital in the face of its legal troubles.

For more than two decades SAC has delivered average annual returns of roughly 30 percent, making it one of the most successful and envied hedge funds in the $2.25 trillion industry. But as it became clear that it was at the center of the government's long running insider trading case, many investors felt uneasy leaving their money with the firm.

U.S. prosecutors filed criminal charges against the firm on July 25 and U.S. Attorney Preet Bharara said at a news conference it had become a "veritable magnet for cheaters." SAC pled not guilty to the charges.

Before the charges were filed, pressure was ratcheting up on SAC. The government arrested Michael Steinberg, a top Cohen lieutenant, in March and the firm paid a record $616 million to settle civil insider trading charges that same month.

Since the charges were filed, there has been some speculation in the hedge fund industry that the government might freeze SAC's assets, but the government said it has no plans to do that.