A federal magistrate refused to grant bail on Monday to a California woman charged with leaking inside information about technology companies.

Prosecutors accuse Winifred Jiau of selling inside information about publicly traded companies, including computer chipmakers Marvell Technology Group Ltd and Nvidia Corp to hedge funds, including the founder of a New York fund that prosecutors did not identify.

Federal prosecutors in New York are also involved in talks that could lead to a possible disposition of charges filed against a former executive with expert network firm Primary Global Research.

In a court filing last week, prosecutors disclosed that, as recently as December 22, they had negotiations with the lawyer for Don Chu, a Primary Global executive, who was arrested November 24 at his New Jersey home.

The prosecutors cited the ongoing negotiations as a reason for requesting additional time to decide whether or not to indict Chu, who was the first person arrested in this new round of expert network cases.

A federal judge has given federal authorities until January 27 to decide whether or not indict Chu.

Prosecutors allege Jiau sold information through an expert network firm, in exchange for more than $200,000 of payments funneled through that firm.

Primary Global has said it used Jiau from September 2006 until December 2008. The period roughly corresponds with the time frame in which prosecutors said Jiau's alleged illegal activity took place.

Jiau also worked for a different research firm, Vista, before Primary Global, her lawyer Mark Goldrosen said outside court on Monday.

Another figure caught up in the widening insider trading probe, Daniel DeVore, also did work for both Primary Global and Vista, according to court papers.

DeVore, a former Dell Computer employee, has pleaded guilty and is cooperating with the government.

A representative for Guidepoint Global, which acquired Vista in 2009, could not immediately be reached.

Last week a different magistrate granted Jiau $250,000 bail, but she was held in a California jail over the weekend because the person who initially agreed to co-sign the bond pulled out.

Jiau reappeared in court on Monday wearing a yellow prison jump suit and glasses. Assistant U.S. Attorney Wilson Leung argued against releasing her, saying she began pulling out of her driveway as federal agents pounded on her door.

But Goldrosen said Jiau, 43, was on her way to run errands and had not heard the agents. Once she saw them, she fully cooperated, Goldrosen said.

U.S. Magistrate Judge Bernard Zimmerman in San Francisco ordered Jiau detained. She will eventually have to use an airport to make court appearances in Manhattan, Zimmerman said, and could be tempted to flee to Taiwan where she is also a citizen.

I think she is a risk of flight, Zimmerman said.

Zimmerman said he would reconsider the decision to detain Jiau if Goldrosen is able to negotiate a bail agreement with U.S. prosecutors in Manhattan, who are spearheading the case.

I felt her ties (in the United States) were strong, Goldrosen said outside court.

Jiau is scheduled to appear in federal court in San Francisco again on January 12.

The case in U.S. District Court, Northern District of California is U.S. v. Jiau, 10-mj-71093.

(Reporting by Dan Levine and Matthew Goldstein; editing by Richard Chang and Andre Grenon)