Investor George Soros doubled his bet on gold at the end of 2009 amid soaring prices, a filing with the U. S. Securities and Exchange Commission shows.

The filing, made late Tuesday for the financial period ending Dec. 31, comes after Mr. Soros made comments during the World Economic Forum in Davos, Switzerland, in late January calling gold an asset bubble.

Soros Fund Management is reported to own 6.2 million shares of SPDR Gold Trust -- an exchange-traded fund that owns gold bullion - at the end of the year worth $663 a rise from 2.5 million shares at the end of the third quarter.

Soros Fund Management's total holdings are $8.8 billion at the end of the year, increased from $6.2 billion on Sept. 30.

Gold prices during the final three months of 2009 are reported to jump about 22%, touching a record-breaking level of $1,226.30 a troy ounce on the spot market.

Soros also registered a stake of 7.7 million shares of Petrobras's U. S. ADRs, worth $369 million, and a slight increase from the 7.4 million receipts held at the end of the third quarter.

Mr. Soros's SPDR shares contribute for about 1.7% of SPDR's 364.1 million outstanding shares.