The new capital brings the firm's total assets under management to $17.5 billion from $15 billion. The money will go into Third Point's sole fund, according to the person.
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Third Point's Offshore Fund is up 6.4 percent this year through August, according to investor materials. That compares with a 9.9 percent rise for the S&P 500 index. Loeb's annualized return net of fees since inception in December 1996 is 17.7 percent, compared with 7.6 percent for the S&P 500 over the same period.
Today, the fund has about 62 percent of its capital in stocks, mostly of companies over $10 billion. Third Point has about 27 percent of the portfolio exposure in credit, according to the materials.
—By CNBC's Lawrence Delevingne