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John Paulson is back in the mortgage business

John Paulson
David Grogan | CNBC

Hedge fund manager John Paulson already made nearly $5 billion betting against the low-quality mortgage market when it collapsed during the financial crisis. Some called it "the greatest trade ever."

Now, Paulson is hoping to make even more money by betting on the same types of securities again.

His $21 billion Paulson & Co. has taken a "significant" minority position in bankrupt mortgage company ResCap, according to The New York Post.

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The ResCap Liquidating Trust was created when the Ally Financial-owned mortgage servicing company went bankrupt in 2012. In order to get as much money for its investors as possible, the trust has filed suits against banks and other financial firms from which it bought many of the faulty mortgages in its portfolio.

The stake was confirmed to by a person familiar with the situation. A spokesman for Paulson declined to comment.

The investment already appears to be paying off. Paulson acquired part of its ResCap stake from troubled bond insurer MBIA for $8 a share, according to the Post. It trades at more than $14 today.

According to the Post report, the trust could recover up to $3.6 billion of its $9 billion in claims.

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Paulson does not control the entity or its lawsuits despite its a stake and its recent appointment of one of five board members for the trust.

Paulson has performed well this year and in 2013 after large losses in 2011 and 2012. The Paulson Credit Opportunities fund is up 8.39 percent and the Paulson Advantage fund gained 9.43 percent through February this year, according to a report by HSBC Alternative Investment Group. Paulson & Co. was also named hedge fund firm of the year at the 2013 Absolute Return Awards in February.

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