“When oil prices spiked last summer to $147 a barrel, the biggest corporate casualty was oil pipeline giant Semgroup Holdings, a $14 billion (sales) private firm in Tulsa, Okla. It had racked up $2.4 billion in trading losses betting that oil prices would go down, including $290 million in accounts personally managed by then chief executive Thomas Kivisto. . . .
But now some of the people involved in cleaning up the financial mess are suggesting that Semgroup’s collapse was more than just bad judgment and worse timing. There is evidence of a malevolent hand at work: oil price manipulation by traders orchestrating a short squeeze to push up the price of West Texas Intermediate crude to the point that it would generate fatal losses in Semgroup’s accounts. . . .
What’s the evidence of this? Much is circumstantial. Proving oil-trading manipulation is difficult. But numerous people familiar with the events insist that Citibank, Merrill Lynch and especially Goldman Sachs had knowledge about Semgroup’s trading positions from their vetting of an ill-fated $1.5 billion private placement deal last spring. “Nothing’s been proven, but if somebody has your book and knows every trade, it would not be difficult to bet against that book and put the company into a tremendous liquidity squeeze,” says John Tucker, who is representing Kivisto.
What’s known for sure is that Goldman Sachs, through J. Aron & Co., its commodities trading arm, was in prime position to use such data–and profited handsomely from Semgroup’s fall. J. Aron was Semgroup’s biggest counterparty, trading both physical oil flowing through pipelines and paper oil, in the form of options and futures.” (Read more from forbes.com)