(Bloomberg News) Silver futures fell, heading for the biggest three-day drop since 2008, and gold also retreated amid a report Soros Fund Management LLC sold precious-metal assets.

Soros Fund Management sold some holdings because of a reduced risk of deflation, according to the Wall Street Journal, which cited unidentified people close to the matter. Michael Vachon, a spokesman for Soros, declined to comment. The fund held shares in the SPDR Gold Trust, the biggest exchange-traded product backed by gold, and the iShares Gold Trust at the end of 2010, U.S. Securities and Exchange Commission filings show.

Silver futures fell as much as 5% to $40.465 an ounce on the Comex exchange in New York. The contract was at $41.72 as of 6 a.m. local time, for a three-day decline of 14%. Margin requirements were raised 38% in since April 26. Gold futures retreated 0.2% to $1,537 an ounce.

"Some small, speculative players had to trim their silver positions as they couldn't afford to pay for such margins," said Jerome Berset, a portfolio manager at Palaedino Asset Management SA in Geneva, which has 1 billion euros ($1.49 billion) in assets and has maintained holdings in gold and silver. "For long-term players with fundamental views, this may be a good time to get in for both silver and gold."

The decade-long bull market in gold and silver attracted fund managers from Soros to John Paulson and spurred central banks to add to their reserves for the first time in a generation. Investors in exchange-traded products backed by gold accumulated more metal than all but four central banks, while silver holdings are equal to more than eight months of global mine supply, according to data compiled by Bloomberg.

Gold Reaches Record

Gold reached a record $1,577.57 an ounce on May 2, a sixfold gain since prices bottomed in August 1999. Spot silver rose to an all-time high of $49.79 an ounce on April 25, a 12-fold advance from the low of $4.04 reached in 2001.

The Soros fund held 4.72 million SPDR Gold Trust shares as of Dec. 31, equal to about 460,000 ounces, an SEC filing on Feb. 14 showed. It also owned 5 million shares in the iShares Gold Trust, equal to about 48,800 ounces. The firm had 19,900 shares in Pan American Silver Corp., a Vancouver-based company mining the metal in Mexico, Peru, Argentina and Bolivia. There were also stakes in Barrick Gold Corp., Kinross Gold Corp. and Novagold Resources Inc., the filing shows.

Soros described gold at the World Economic Forum's meeting in Davos, Switzerland, in January last year as "the ultimate asset bubble." In a Nov. 15 speech in Toronto the 80-year-old said conditions for the metal to keep rising were "pretty ideal" and at this year's Davos forum he said the boom in commodities may last "a couple of years" longer.

Paulson Holding

Paulson & Co.'s holding was 31.5 million shares in SPDR Gold at the end of December, an SEC filing shows.

Passport Capital Management LLC also sold some gold holdings to lock in profit, the Wall Street Journal reported, citing a person close to the fund. Passport Capital held 3 million put options on SPDR Gold shares and 28,100 shares in Barrick Gold as of Dec. 31, according an SEC filing. Two phone calls outside of normal office hours to John Burbank, founder of Passport Capital, weren't answered.

CME Group Ltd., the owner of the Comex exchange, said this week the minimum amount of cash that must be deposited when borrowing from brokers to trade silver futures will rise to $16,200 per contract at the close of business yesterday from $14,513. A year ago, the margin was $4,250.

"Silver is often the lead indicator for changes in trends, or at least for corrections," David Wilson, an analyst at Societe Generale SA, wrote in a note. After futures rallied to a record $50.35 an ounce in January 1980, prices dropped 78% in four months.

From the start of this year to the end of April, silver futures rallied 57% and were the best performer among the 24 raw materials tracked by the Standard & Poor's GSCI Index.

Silver assets held in exchange traded products fell 1.1% to 15,169.80 metric tons yesterday, while gold holdings stood little changed at 2,069.78 tons, according to data compiled by Bloomberg.