Public offerings of common stock often result in dilution of equity for existing shareholders. This dilution can lead to a decrease in stock price as the market adjusts to the increased number of shares available and the perceived reduction in the value of each share. Given that this is a direct action by AMSC, it is highly relevant to the company's stock and is of significant importance to investors. The confidence level is high due to the typical market reaction to such announcements, although the exact impact will depend on the details of the offering and market conditions.