(Adds detail on Soros Fund Management's decision)
By Jennifer Ablan
Nov 20 (Reuters) - Bill Gross just got a huge vote of confidence from legendary investor George Soros.
Soros Fund Management LLC, which Soros chairs, has invested $500 million in an account run by Gross at Janus Capital Group Inc, the Denver-based firm said on its website on Thursday.
The money will be managed through a private investment vehicle named Quantum Partners LP and invested in a separate account, Janus said. The portfolio will follow the strategy that Gross is employing in his Janus Global Unconstrained Bond fund , which has $443 million in assets under management.
Soros Fund Management approached Gross after he resigned from Pimco in late September, a person familiar with the situation said.
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.
"We are honored to be managing a new unconstrained strategic account for Soros Fund Management LLC," Gross tweeted. "I & my team will manage your new unconstrained strategic acct. 24h/day. An honor to be chosen & an honor to be earned as well."
Soros Fund Management's chief investment officer Scott Bessent met with Gross, the source said, adding that the fund considers Gross a legend.
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.
Janus Capital Group posted $1.1 billion in net inflows in October, the largest net deposits this year, after hiring Gross, one of the bond market's most renowned investors.
The Janus Global Unconstrained portfolio, which Gross started managing in October, has attracted an estimated $364 million in client deposits in the first full month since Gross' arrival, bringing assets to $442.9 million through Oct. 31, according to Morningstar data on Monday.
Janus shares hit session highs of $15.07 in rising volume in the wake of the Soros news. The shares closed nearly 2 percent higher at $15.03 on Thursday. (Editing by James Dalgleish, Bernadette Baum and Andre Grenon)