Schilling, whose Providence-based 38 Studios filed for bankruptcy in June, listed the sock as collateral to Bank Rhode Island in a September filing with the Massachusetts Secretary of State's office. The sock is on display at the National Baseball Hall of Fame and Museum in Cooperstown, N.Y.
Schilling also listed a baseball hat believed to have been worn by New York Yankees great Lou Gehrig and his collection of World War II memorabilia, including some the filing said is being held at the National World War II Museum.
Messages left for Schilling were not immediately returned. Hall of Fame spokesman Brad Horn declined to say whether Schilling has asked for the sock, on loan since 2005, to be returned.
The Boston Globe first reported the filing Thursday. It said Schilling personally guaranteed as much as $9.6 million in loans from Bank Rhode Island and $2.4 million in loans from Citizens Bank related to 38 Studios.
Schilling, who also pitched for Baltimore, Houston, Philadelphia and Arizona and who won the World Series three times, is perhaps best remembered for pitching Game 6 of the 2004 American League Championship Series with an injured ankle that bloodied his sock. The sock now listed as collateral was stained during the second game of the World Series, which the Red Sox won that year for the first time in 86 years.
Richie Russek, owner of the Westhampton, N.Y.-based Grey Flannel Auctions, who is featured on The Discovery Channel series "All Star Dealers," estimated the bloody sock could sell for between $50,000 and $100,000, but stressed there is nothing comparable that has ever been auctioned off. He said the Gehrig cap would likely fetch at least $150,000.
38 Studios - which was lured to Rhode Island from Massachusetts with a $75 million state loan guarantee - had a spectacular collapse. Its financial problems spilled into public view last spring when it missed a $1.1 million payment to the Economic Development Corp. Within weeks, 38 Studios had laid off its nearly 300 employees in Providence and another 100 at an affiliate in Maryland ahead of a bankruptcy filing in June.
The firm owes $150.7 million and has assets of $21.7 million, according to court filings. 38 Studios Baltimore made a separate bankruptcy and owes more than $121.4 million, with assets of more than $335,000.
The state of Rhode Island, by far the firm's largest creditor, is now likely on the hook for some $100 million related to the loan guarantee deal, including interest. The company's assets are scheduled to be auctioned off.
Schilling has conceded he was "absolutely" part of the reason the company failed. But he repeatedly accused Gov. Lincoln Chafee, who was sharply critical of the loan guarantee, of having an agenda that hurt 38 Studios. He called Chafee a "dunce of epic proportions" and a "buffoon."
Chafee, an independent, has said he did everything he could to help the company.
Schilling also recently put his 20-room home on 26 acres in Medfield, Mass., on the market for $3.45 million. The house, which has a heated pool with waterfall, a beach volleyball court, batting and pitching cages and a putting green, was also listed for sale in 2008.
Schilling has said he invested as much as $50 million in 38 Studios and has lost all his baseball earnings.