Western Refining (NYSE: WNR) owns and operates four oil refineries in the Southwest United States, with a capacity of 234,000 barrels per day (bpd). Western Refining's profits are determined primarily by the cost of refining crude-oil and the prices at which the Company can sell those refined products. However, Western Refining has increased the amount of cheaper, low-grade crude oil that its refineries can process in anticipation of higher crude prices and lower profit margins in the future.^[1]

Western Refining faces new competition from Gulf Coast oil companies, which have begun to supply the Southwest United States through the Longhorn Pipeline. In response,Western Refining has expanded its refining capacity through acquisitions of other independent refiners. In particular, Western Refining’s 2007 purchase of Giant Inc. doubled their refinery capacity.

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