The US Securities and Exchange Commission (SEC) yesterday approved a proposal from NYSE Arca relating to use of derivative instruments by AdvisorShares Global Echo ETF which effectively lifts the embargo on the use of synthetic exchange-traded funds (ETFs) in the US market. The embargo has been in place since March 2010 when the regulator announced a review to evaluate the use of derivatives by mutual funds, ETFs, and other investment companies. The move follows the US watchdog’s rejection last