Shell and Phillips 66 have bought 6.4million barrels of oil collectively from the Strategic Petroleum Reserve.
The purchase was revealed in Department of Energy documents on Tuesday.
Oil major Shell bought 6.2million barrels of oil and Phillips 66 bought 200,000 barrels on January 18th, according to the document.
The federal government had held to sale in a bid to fund a revamp of the emergency oil stash which is currently stored in salt caverns in Louisiana and Texas along the Gulf Coast.
Shell will take delivery of 1.7million barrels of oil to a vessel.
Meanwhile, the remainder of the barrels are slated for pipeline delivery.
A spokesman for Shell has decline to comment on whether the company plans to export the crude.