The auction of oil from the Strategic Petroleum Reserve brought in $3.28 billion of bids, an average of $107.19 a barrel, according to a list of the winning bidders. But crude oil prices on futures markets, responding in part to easing economic concerns, have already rebounded to levels that preceded President Obama’s announcement of a drawdown from reserves.

The nation’s biggest independent oil refiner, Valero, won the largest chunk in the auction, purchasing 6.9 million barrels, or 22.5 percent of the total, according to an Energy Department table. Other winning bids went to major oil refiners and oil trading firms, including Shell’s U.S. trading arm and Geneva-based Vitol. Barclays and J.P. Morgan Chase also submitted winning bids.

Valero spokesman Bill Day said it was “convenient” and “financially attractive” to buy oil from the Strategic Petroleum Reserve because Valero is the largest refiner along the Gulf of Mexico and the reserves are located in giant salt caverns along the coast.

Obama ordered the release of 30 million barrels of oil from the reserves, an amount to be matched by other members of the International Energy Agency in an effort to tamp down prices and offset production lost as a result of fighting in Libya.

But the IEA has since announced that 20 million barrels will be “released” by lowering requirements for commercial stockpiles. Goldman Sachs noted in a report to investors that industry stockpiles are already higher than government requirements and the IEA move, therefore, will probably have little effect. It said that including U.S. sales, the total sales from government inventories would be at most 39 million barrels. The firm reduced its estimate of how much the releases would lower prices.

The price of New York Mercantile Exchange’s benchmark crude, West Texas Intermediate, fell 48 cents to $94.94 a barrel Friday. On Thursday, WTI closed a penny above the level it was the day before Obama’s announcement. The price of the more widely used Brent grade of crude oil in London fell 71 cents to $111.77 a barrel on Thursday.

Valero said it paid a price closer to the Brent benchmark because the price of West Texas Intermediate has been depressed by transportation bottlenecks and storage shortages in Cushing, Okla., the terminal used by the New York Mercantile Exchange.