EX-99.1

                                                                    Exhibit 99.1
                                                                    ------------

                                   Footnotes
                                   ---------

(1)  The stockholder is Warburg Pincus  Ventures,  L.P.  ("Ventures").  Ventures
     beneficially  owns  3,531,328  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") a
     subsidiary of Warburg  Pincus & Co. ("WP") a New York general  partnership.
     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. Ms. Weatherman does not directly own any shares of common stock of
     the Issuer.

(2)  On July 12, 2005,  Ventures  distributed an aggregate of 2,973,526 shares
     of Common Stock to its partners.

(3)  Price not applicable.

EX-99.2

                                                                    Exhibit 99.2
                                                                    ------------
List of Filers
- --------------


Designated Filer:                       Warburg Pincus Ventures, L.P.
Issuer & Ticker Symbol:                 Kyphon Inc. [KYPH]
Date of Event Requiring Statement:      July 12, 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.


                      By:   /s/ Scott A. Arenare                         7/14/05
                           ---------------------------------------       -------
                           Name:   Scott A. Arenare                         Date
                           Title:  Partner




                      WARBURG PINCUS LLC


                      By:   /s/ Scott A. Arenare                         7/14/05
                           ---------------------------------------       -------
                           Name:   Scott A. Arenare                         Date
                           Title:  Member




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

                      By:   /s/ Scott A. Arenare                         7/14/05
                           ---------------------------------------       -------
                           Name:   Scott A. Arenare                         Date
                           Title:  Partner


                      ELIZABETH WEATHERMAN


                      By:   /s/ Scott A. Arenare                         7/14/05
                           ---------------------------------------      --------
                           Name:   Scott A. Arenare                         Date
                           Title:  Attorney-in-Fact for Director
                                   Elizabeth Weatherman pursuant to
                                   the Power of Attorney dated
                                   May 24, 2004 attached hereto, as
                                   Exhibit 24

EX-24

Exhibit 24
- ----------

                                POWER OF ATTORNEY





          The undersigned  hereby  constitutes and appoints each of Scott A.
Arenare, Timothy J. Curt,  and Steven G.  Schneider, acting together or
individually, his/her true and lawful attorney-in-fact to:

(1)  execute for and on behalf of the undersigned Forms 3, 4, and 5,
     together with any amendments thereto, in accordance with the Securities
     Exchange Act of 1934, as amended, and the rules thereunder;

(2)  do and perform any and all acts for and on behalf of the undersigned
     which may be necessary or desirable to complete the execution of any
     such Forms and the filing thereof with the United States Securities and
     Exchange Commission and any other person as may be required by law; and

(3)  take any other action of any type whatsoever in connection with the
     foregoing which, in the opinion of such attorney-in-fact, may be of
     benefit to, in the best interest of, or legally required by, the
     undersigned, it being understood that the documents executed by such
     attorney-in-fact on behalf of the undersigned pursuant to this power of
     attorney shall be in such form and shall contain such terms and
     conditions as such attorney-in-fact may approve in his discretion.


          The undersigned hereby grants to each such attorney-in-fact full power
and authority to do and perform all and every act and thing whatsoever
requisite, necessary and proper to be done in the exercise of any of the rights
and powers herein granted, with full power of substitution or revocation, hereby
ratifying and confirming all that such attorney-in-fact, or his substitute or
substitutes, shall lawfully do or cause to be done by virtue of this power of
attorney and the rights and powers herein granted. The undersigned acknowledges
that the foregoing attorneys-in-fact, in serving in such capacity at the request
of the undersigned, are not assuming any of the undersigned's responsibilities
to comply with the Securities Exchange Act of 1934, as amended.


          This Power of Attorney shall remain in full force and effect until
revoked in writing by the undersigned or his/her attorney-in-fact.


          IN WITNESS WHEREOF, the undersigned has executed this Power of
Attorney this 15th day of May, 2004.





                                        Signature:  /s/ Elizabeth H. Weatherman
                                                   -----------------------------

                                        Print Name: Elizabeth H. Weatherman