Between January and the end of March, according to a regulatory filing, Paulson's New York-based Paulson & Co. took a new position of 17 million shares in mortgage insurer MGIC Investment Corp. He raised his stakes in two other mortgage insurers, more than tripling his holdings in Radian Group Inc. to 11.5 million shares from 3.5 million shares, and raising his holdings in Genworth Financial Inc to 9 million shares from 3.9 million shares.

Paulson, like other investment managers, disclosed those and other holdings in a so-called 13-F report filed with the U.S. Securities and Exchange Commission on Wednesday. While such filings are backward looking and do not always reflect what a manager owns now, they do often point to trends.

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Paulson's $18 billion, New York-based hedge fund is well known for having bet against the overheated housing market several years ago. Now Paulson is clearly betting that growth will improve and that a strong recovery in the housing market will continue.

While the 13-F filings do not show exactly which of Paulson's portfolios own these names, their stock price gains this year likely fueled the strong run in Paulson's $1.9 billion Recovery fund.

The portfolio gained 14 percent during the first quarter and surged more to be up 21 percent through the end of April, marking one of the very best performances in the industry, where funds on average have gained only roughly 5 percent this year.

Paulson's best-known funds — including the Advantage funds, which lost money in 2012 and 2011 — got off to a strong start in 2013. The Advantage Plus fund was up 8.3 percent during the first quarter while the Paulson Credit Opportunities fund was up 10.4 percent, and merger arbitrage funds Paulson International and Paulson Enhanced gained 5.5 percent and 11.6 percent, respectively, people familiar with the numbers said.

In the tight-knit hedge fund industry, Paulson is largely known as a merger-arbitrage specialist and during the first quarter he took on new positions where he might see an event in the future that would push up the share price.

After having owned a chunk of Citigroup a few years ago, Paulson took a new position in the stock during the first quarter. He also bought 1 million shares of H.J. Heinz and now owns 2.8 million of Vodafone's American depositary receipts. The hedge fund also reported a new 2.69 million-share stake in Hess Corp.

On the other hand, the regulatory filing showed that he cut some stakes as well, including Hartford Financial Services Group . The fund owned 10 million Hartford shares at the end of the first quarter, down from 18 million shares. He also cut his stake in Delphi Automotive by 36 percent to 8.7 million shares.

Meanwhile Paulson, who has long owned gold and gold miners in part because he believes that inflation will eventually pick up again in light of the easy money policies of central banks, kept his stakes in the miners largely steady, the filing shows.

Paulson's gold-oriented fund, where his own money makes up the bulk of the roughly $500 million in assets, dropped 28 percent during the quarter and tumbled more in April, people familiar with the returns said.

Robbed: Secret ‘Financial War’ Will Wipe Out Your Wealth, Warns Pentagon Adviser