PANews reported on December 3 that the U.S. Securities and Exchange Commission (SEC) has issued a series of warning letters to some of the country's most prolific providers of highly leveraged exchange-traded funds (ETFs), effectively halting the launch of products aimed at offering two or three times the daily return on stocks and commodities. In nine nearly identical letters released Tuesday, the SEC informed companies including Direxion, ProShares, and Tidal that it would not proceed with reviews of proposed offerings until key issues were resolved. The regulator's core concern is that these funds' risk exposure may exceed the SEC's limits on the risks a fund can take relative to its assets. The letters instruct fund managers to either modify their investment strategies or formally withdraw their applications.