EX-99.1

                                                                  Exhibit 99.1.

                               Continuation Sheet

                                    Footnotes

(1)      The stockholder is Warburg Pincus Ventures, L.P. ("Ventures"). Ventures
         beneficially owns 6,504,854 shares of common stock ("Common Stock") of
         Kyphon Inc. (the "Issuer"). The sole general partner of Ventures is
         Warburg Pincus Partners LLC, a New York limited liability company ("WPP
         LLC") and a subsidiary of Warburg Pincus & Co. ("WP"). Warburg Pincus
         LLC (formerly E.M. Warburg Pincus & Co., LLC), a New York limited
         liability company ("WP LLC"), manages Ventures. By reason of the
         provisions of Rule 16a-1 of the Exchange Act, WPP LLC, WP and WP LLC
         may be deemed to be the beneficial owners of the Common Stock held by
         Ventures, although WPP LLC, WP and WP LLC disclaim beneficial ownership
         of the Common Stock except to the extent of any indirect pecuniary
         interest therein. Ms. Weatherman, a director of the Issuer, is a
         general partner of WP and a member of WP LLC. As such, Ms. Weatherman
         may be deemed to have an indirect pecuniary interest (within the
         meaning of Rule 16a-1 of the Exchange Act) in an indeterminate portion
         of the shares beneficially owned by Ventures, WP LLC, WP and WPP LLC.
         Ms. Weatherman disclaims beneficial ownership of such shares except to
         the extent of any indirect pecuniary interest therein.

(2)      On June 13, 2005, Ventures distributed an aggregate of 2,021,998 shares
         of Common Stock to its partners.

(3)      Price not applicable.

EX-99.2

                                                                 Exhibit 99.2

Designated Filer:                   Warburg Pincus Ventures, L.P.
Issuer & Ticker Symbol:             Kyphon Inc. [KYPH]
Date of Event Requiring Statement:  June 13, 2005

1.    Name: Warburg Pincus Ventures, L.P.
      Address: 466 Lexington Avenue
      New York, New York  10017

2.    Name: Warburg Pincus & Co
      Address: 466 Lexington Avenue
      New York, New York  10017

3.    Name: Warburg Pincus LLC
      Address: 466 Lexington Avenue
      New York, New York  10017

4.    Name: Warburg Pincus Partners LLC
      Address: 466 Lexington Avenue
      New York, New York  10017

5.    Name: Elizabeth Weatherman
      Address: 466 Lexington Avenue
      New York, New York  10017







                                       WARBURG PINCUS & CO.

                                             /s/ Scott A. Arenare
                                       By:  ----------------------    6/15/05
                                            Name:  Scott A. Arenare   -------
                                            Title:  Partner           Date


                                       WARBURG PINCUS LLC

                                             /s/ Scott A. Arenare
                                       By:  ----------------------    6/15/05
                                            Name:  Scott A. Arenare   -------
                                            Title:  Member            Date



                                       WARBURG PINCUS PARTNERS LLC
                                           By:  Warburg Pincus & Co.,
                                               its Managing Member

                                             /s/ Scott A. Arenare
                                       By:  ----------------------    6/15/05
                                            Name:  Scott A. Arenare   -------
                                            Title:  Partner           Date


                                       ELIZABETH WEATHERMAN

                                             /s/ Scott A. Arenare
                                       By:  ----------------------    6/15/05
                                            Name:  Scott A. Arenare   -------
                                            Title:  Partner           Date