George Soros’ investment firm has pulled a $500 million investment with Bill Gross that it made last year after the bond manager left Pacific Investment Management Co. to run a new fund at Janus Capital Group Inc., the Wall Street Journal reported, citing industry data and a person familiar with the matter.

The money invested by Soros Fund Management was held in a separate, institutional account that followed a similar strategy as Gross’ mutual fund, the newspaper said.

But a lot has changed since last year, Barron's reported. "Gross has struggled with performance issues with his Janus Global Unconstrained Bond Fund (JUCTX), which has languished near the bottom quartile in its category. Gross also launched a vituperative lawsuit at Pimco last month," Barron's reported.

Gross’ fund at Janus, the $1.38 billion Janus Global Unconstrained Bond Fund, declined 1.2 percent this year, trailing 71 percent of similar funds, according to data compiled by Bloomberg.

"Industry data provider eVestment LLC, which tracks institutional accounts at fund firms, confirmed that $490 million wasn’t reported by Janus in separate accounts managed by the firm between the second and third quarter," WSJ.com reported.

The trade publication Pension & Investments earlier reported on the $490 million outflow, but P&I didn’t identify the party that made the withdrawal, WSJ.com reported.

The withdrawal by Soros is particularly significant for Gross as his Janus Global Unconstrained Bond Fund holds more than $700 million of Gross' personal money, Reuters reported.

Soros Fund Management's Chief Investment Officer Scott Bessent last year approached Gross after he resigned from Pimco in late September, the source said, adding that the fund had considered Gross a legend. Gross co-founded Pimco in 1971 and built it into one of the largest investment firms in the world, managing $2 trillion of pension, endowment and retirement money.

Soros Fund Management, founded in 1969 by George Soros, was reported to be one of the most profitable firms in the hedge fund industry in 2010, averaging a 20 percent annual rate of return over four decades.</p><p>Janus shares were up nearly 2 percent at $15.79 on Monday. A spokeswoman at Janus declined to comment on the Soros news.

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