The U.S. Securities and Exchange Commission (SEC) and the Commodity Futures Trading Commission (CFTC) are investigating the most popular exchange-traded fund tracking crude oil prices, the United States Oil Fund, to ascertain if the fund has managed to properly disclose to investors the risks, Bloomberg reported on Friday, citing three sources familiar with the issue. The United States Oil Fund LP (NYSEARCA: USO), one of the most popular oil-tracking ETFs for retail investors, was said to be one of the reasons for the historic plunge in May WTI Crude futures on April 20, a day before the May contract expired on April ... (full story)