Fuel Tech, Inc. (NASDAQ:FTEK - Get Free Report) saw a large increase in short interest in the month of September. As of September 15th, there was short interest totaling 362,655 shares, an increase of 166.3% from the August 31st total of 136,160 shares. Approximately 1.3% of the shares of the company are short sold. Based on an average daily trading volume, of 308,187 shares, the short-interest ratio is currently 1.2 days.