Billionaire investor George Soros' hedge fund saw the value of its holdings fall slightly to $8.75 billion as of the end of the first quarter, as he added to his position in energy companies.

Soros Fund Management reported holdings of $8.75 billion as of the end of the first quarter, down from the $8.85 billion reported at the end of last year, according to a filing late Monday with the U.S. Securities and Exchange Commission.

The fund increased its position in several energy companies, including one of its largest holdings, Petroleo Brasileiro S/A (PBR), which rose to 9.1 million shares, or $405 million, from 7.7 million shares, or $368.7 million, in the fourth quarter.

Soros also added to his existing position in Suncor Energy Inc. (SU), raising it to 8.7 million shares, or $264.1 million. In the fourth quarter, his position in the company was 7.2 million shares, or $252.9 million. He also bought 5.9 million shares, valued at $81.1 million, of Cobalt International Energy Inc. (CIE) during the first quarter.

Soros, who took a significant position in SPDR Gold Trust (GLD) in the fourth quarter, lowered his position to 5.2 million shares, or $566.9 million. He initially reported a position of 6.2 million, or $663 million at the end of 2009.

The fund halved its stake in pharmaceutical giant Pfizer Inc. (PFE), with its position falling to 5.3 million shares, or $91.4 million, from 11.6 million shares, or $210.5 million, at the end of the fourth quarter.

Soros also bought 19.4 million convertible notes of ADC Telecommunications Inc. (ADCT), valued at $16.5 million, and 16.4 million convertible notes in Global Crossing Ltd. (GLBC), valued at $16.4 million. Both are new positions to the fund.

Last week, Alibaba.com Ltd. (1688.HK) disclosed that Soros' fund became one of the top three shareholders in the Chinese online business platform operator. According to filings with the Hong Kong Stock Exchange, only Alibaba.com's parent, Alibaba Group, and U.S. Internet giant Yahoo Inc. (YHOO) are listed as major shareholders of Alibaba.com.

Many investors that manage more than $100 million are required to file 13-Fs with their stock holdings 45 days after the end of a given quarter, giving the public its freshest possible glimpse into the portfolios of well-known money managers. Most hedge-fund managers and others wait until the last possible moment to make these filings. Because of the weekend and Presidents' Day, the fourth-quarter deadline is Tuesday.

-By Roger Cheng, Dow Jones Newswires; 212-416-2153; roger.cheng@dowjones.com