Quantinuum Inc. (Nasdaq: QNT) ("Quantinuum") today announced the closing of its upsized initial public offering of 28,000,000 shares of its Class A common stock at an initial public offering price of $60.00 per share. All of the shares were offered by Quantinuum. The aggregate gross proceeds from the offering, before deducting underwriting discounts and commissions and other offering expenses were $1.68 billion. Quantinuum's Class A common stock is listed on the Nasdaq Global Market under the ticker symbol "QNT."

J.P. Morgan and Morgan Stanley (in alphabetical order) acted as joint lead active book-running managers for the offering; Jefferies and Evercore ISI also acted as active book-running managers; BofA Securities, UBS Investment Bank, Cantor, Mizuho, Needham & Company, Societe Generale and TD Cowen acted as joint-book running managers; and Craig-Hallum and Rosenblatt acted as co-managers for the offering.

A registration statement relating to this offering was declared effective by the Securities and Exchange Commission (the "SEC") on June 3, 2026. A prospectus relating to and describing the terms of the offering has been filed with the SEC and is available on the SEC's website at www.sec.gov. The offering is being made available only by means of a prospectus. Copies of the prospectus may be obtained from: J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717 or by email at prospectus-eq_fi@jpmchase.com and postsalemanualrequests@broadridge.com; Morgan Stanley & Co. LLC, 180 Varick Street, 2nd Floor, New York, New York 10014, Attention: Prospectus Department or by email at prospectus@morganstanley.com; Jefferies LLC, Attn: Equity Syndicate Prospectus Department, 520 Madison Avenue, New York, New York 10022, by telephone at (877) 821-7388 or by email at Prospectus_Department@Jefferies.com; or Evercore Group L.L.C., Attention: Equity Capital Markets, 55 East 52nd Street, 35th Floor, New York, New York 10055, by telephone at 888-474-0200 or by email at ecm.prospectus@evercore.com.

This press release does not constitute an offer to sell or the solicitation of an offer to buy these securities, nor shall there be any 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 any such state or jurisdiction.