Regulators had long classified a private Swiss energy conglomerate called Vitol as a trader that primarily helped industrial firms that needed oil to run their businesses. But when the Commodity Futures Trading Commission examined Vitol's books last month, it found that the firm was in fact more of a speculator, holding oil contracts as a profit-making investment rather than a means of lining up the actual delivery of fuel. Even more surprising to the commodities markets was the massive size of Vitol's portfolio -- at one point in July, the firm held 11 percent of all the oil contracts on the regulated New York Mercantile Exchange. The discovery revealed how an individual financial player had gained enormous sway over the oil market without the knowledge of regulators. Other CFTC data showed that a significant amount of trading activity was concentrated in the hands of just a few speculators. The CFTC ... now reports that financial firms speculating for their clients or for themselves account for about 81 percent of the oil contracts on NYMEX, a far bigger share than had previously been stated by the agency. That figure may rise in coming weeks as the CFTC checks the status of other big traders. Some lawmakers have blamed these firms for the volatility of oil prices, including the tremendous run-up that peaked earlier in the summer. It is now evident that speculators in the energy futures markets play a much larger role than previously thought, and it is now even harder to accept the agency's laughable assertion that excessive speculation has not contributed to rising energy prices," said Rep. John D. Dingell (D-Mich.).

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