Amphastar Pharmaceuticals, Inc. (NASDAQ:AMPH – Get Free Report) was the target of a significant increase in short interest in November. As of November 15th, there was short interest totalling 2,890,000 shares, an increase of 15.6% from the October 31st total of 2,500,000 shares. Currently, 8.1% of the shares of the stock are sold short. Based […]