Shares of Aspen Aerogels (NYSE: ASPN) plummeted by 5.46% on October 21, 2024, after the company announced a public offering of 4,250,000 shares of its common stock. The stock plunge occurred shortly after the announcement was made around 12:54 PM ET.

In a press release, Aspen Aerogels stated that it plans to use the net proceeds from the offering for working capital, capital expenditures, and general corporate purposes. The company also granted the underwriters of the offering a 30-day option to purchase an additional 637,500 shares of common stock.

The public offering is expected to dilute the company's existing shareholdings, as it increases the total number of outstanding shares. Such share dilution typically puts downward pressure on a company's stock price, which appears to be the primary reason behind Aspen Aerogels' stock plunge following the announcement.