Castle Biosciences Announces Full Exercise of Underwriters' Option to Purchase Additional Shares of Common Stock

Castle Biosciences, Inc. (Nasdaq: CSTL), announced today that the underwriters of its recently closed underwritten public offering of 2,000,000 shares of its common stock have exercised in full their option to purchase an additional 300,000 shares of common stock at the public offering price of $37.00 per share, less underwriting discounts and commissions. The gross proceeds to Castle Biosciences from the offering, including the shares sold pursuant to the underwriters' option, before deducting the underwriting discounts and commissions and offering expenses, were $85.1 million.

SVB Leerink and Baird were joint book-running managers for the offering and representatives of the underwriters. Canaccord Genuity was passive book-runner and BTIG was co-manager for the offering.

Registration statements relating to these securities have been filed with the Securities and Exchange Commission ("SEC") and became effective on June 24, 2020. The offering was made only by means of a prospectus. A copy of the final prospectus related to the offering may be obtained for free by visiting the SEC's website located at http://www.sec.gov; from SVB Leerink LLC, Attention: Syndicate Department, One Federal Street, 37th Floor, Boston, MA 02110, by telephone: (800) 808?7525, ext. 6218, or by email: [email protected]; or from Robert W. Baird & Co. Incorporated, Attention: Syndicate Department, 777 East Wisconsin Ave., Milwaukee, WI 53202, by telephone: (800) 792-2473, or by email: [email protected].

This press release shall not constitute an offer to sell or a solicitation of an offer to buy, nor shall there be any offer or sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such state or jurisdiction.

About Castle Biosciences

Castle Biosciences (Nasdaq: CSTL) is a commercial-stage dermatologic cancer company focused on providing physicians and their patients with personalized, clinically actionable genomic information to make more accurate treatment decisions.