International Securities Exchange Announces Closing Of Initial Public Offering - Underwriters Exercise Full Over-Allotment Option

The International Securities Exchange, Inc. (NYSE:ISE) today announced the closing of its initial public offering. As part of the offering, ISE sold 4,602,115 shares of Class A common stock, including 602,115 shares upon the exercise in full of the underwriters' over-allotment option, at $18.00 per share. Certain ISE shareholders sold an additional 6,954,590 shares of Class A common stock, including 905,282 shares sold in connection with the underwriters' over-allotment option.

Including the exercise of the over-allotment option, proceeds to the Company, less underwriting discounts and commissions, were approximately $77 million.

ISE's stock began trading on The New York Stock Exchange on March 9, 2005 under the ticker symbol "ISE."

Bear, Stearns & Co. Inc. and Morgan Stanley were joint book-running managers of the offering. Goldman, Sachs & Co., Banc of America Securities LLC, Deutsche Bank Securities, Merrill Lynch & Co. and UBS Investment Bank served as co-managers. Copies of the final prospectus may be obtained from Bear, Stearns & Co. Inc., c/o Prospectus Department, 383 Madison Avenue, New York, NY 10179 or Morgan Stanley, Prospectus Department, 1585 Broadway, New York, NY 10036.