Exhibit 10.729

NOVARTIS AG    WRITTEN CONSENT AND APPROVAL    Effective as of December 5, 2003

STOCK REPURCHASE PLAN

WHEREAS, Section 2.04 (a)(iii) of that certain Governance Agreement dated as of November 20, 1994 between Chiron Corporation ("Chiron" or the
"Company") and Novartis AG (the "Governance Agreement"), requires the consent of Novartis AG in connection with any reclassification, combination, split, subdivision, or redemption, purchase or other
acquisition, directly or indirectly, of any debt or equity securities or other capital stock of the Company;

WHEREAS,
the Company currently has a stock repurchase plan (the "Stock Repurchase Plan") pursuant to which the Company is authorized from time to time to repurchase up to thirty million
five hundred thousand (30,500,000) shares, to substantially offset dilution associated with the operation of its 1991 Stock Option and Employee Stock Purchase Plans; and

WHEREAS,
the Non-Novartis Directors and the Board of Directors of Chiron propose to authorize management to increase the total number of shares authorized for repurchase
under the Stock Repurchase Plan from thirty million five hundred thousand (30,500,000) to thirty-five million five hundred thousand (35,500,000) shares of the Company's Common Stock in
open market transactions through December 31, 2004, subject to approval by Novartis AG;

NOW,
THERFORE, BE IT RESOLVED, that the increase in the number of shares of Chiron Common Stock authorized for repurchase under the Stock Repurchase Plan of Chiron, thereby increasing
the total number of shares of Chiron Common Stock authorized for repurchase under the Plan from thirty million five hundred thousand (30,500,000) to thirty-five million five hundred
thousand (35,500,000) shares, in open market transactions through December 31, 2004, is hereby approved;

AMENDMENTS TO GOVERNANCE AGREEMENT AND BYLAWS

WHEREAS, Sections 2.04 (b)(iv) and (vii) of that certain Governance Agreement dated as of November 20, 1994 between Chiron Corporation
("Chiron" or the "Company") and Novartis AG, requires the approval of a majority of the Investor Directors to amend the Bylaws of Chiron or to establish any committee of the Board of Directors of
Chiron other than as provided in Section 2.03(b)(i) through (v) of the Governance Agreement;

WHEREAS,
Section 2.03(b)(vi) of the Governance Agreement provides that the Board of Directors of Chiron may establish such other committees of the Board as the Board deems
necessary or desirable, provided that such committees are established in compliance with the terms of the Governance Agreement; and

WHEREAS,
Section 3.11 of Chiron's Bylaws currently provides for the establishment of five committees of the Board, and the Board has deemed it appropriate and in the best
interests of Chiron to amend Section 3.11 of the Bylaws and Section 2.03 (b) of the Governance Agreement to establish an additional committee of the Board called the "Finance
Committee," which committee shall be established and constituted with such powers and authority in accordance with Sections 2.03(a) and (c) of the Governance Agreement;

NOW,
THEREFORE, BE IT RESOLVED, that the amendments to Section 2.03(b) of the Governance Agreement and Section 3.11 of Chiron's Bylaws in substantially the form attached
hereto asAnnex 1andAnnex 2, are hereby approved;

IN
CONSIDERATION OF THE FOREGOING, Novartis AG hereby approves the (a) increase in the number of shares of Chiron Common Stock authorized for repurchase under the Stock Repurchase

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Plan
of Chiron, thereby increasing the total number of shares of Chiron Common Stock authorized for repurchase under the Plan from thirty million five hundred thousand (30,500,000) to
thirty-five million five hundred thousand (35,500,000) shares, in open market transactions through December 31, 2004; and (b) establishment of the Finance Committee of
Chiron's Board of Directors, and corresponding amendments to the Governance Agreement with Chiron and Chiron's Bylaws, effective as of December 5, 2003.

| |  | NOVARTIS AG              
| |  | -------------------------
| |  | By:                      
| |  | Its: authorized signatory
| |  | By:                      
| |  | Its:                     
| |  |                          

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ANNEX 1

CHIRON CORPORATION  Governance Agreement Dated November 20, 1994 with Novartis AG

Section 2.03(b)
of the Governance Agreement dated November 20, 1994 with Novartis AG (the "Governance Agreement") is hereby amended, effective as of December 5, 2003, to adda new subsection, 2.03(vi) to
read in its entirety, as follows:

"(vi) a
Finance Committee, consisting of at least three members of the Board, which shall assist the Board in fulfilling its responsibility for oversight with respect to Chiron's
capital structure, financing and investment strategies and financial management, subject to applicable law and limits imposed by the Governance Agreement, the Company's Restated Certificate of
Incorporation, as amended from time to time, and by action of the Board; and"

Subsection
2.03(vi) is herebyre-designatedas subsection 2.03(vii) to read in its entirety, as follows:

"(vii) such
other committees as the Board of Directors deems necessary or desirable; provided that such committees are established in compliance with the terms of this
Agreement."

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ANNEX 2

CHIRON CORPORATION  Bylaws, as amended

Section 3.11
of the Bylaws of Chiron Corporation is hereby amended, effective as of December 5, 2003, to read in its entirety, as follows:

3.11Committees.Section 2.03 of the Governance Agreement provides that the following committees of the
Board of Directors shall be formed and administered: (i) an Audit Committee; (ii) a Nominating and Corporate Governance Committee; (iii) a Strategic Planning Committee;
(iv) a Compensation Committee; (v) a Stock Option Plan Administration Committee; and (vi) a Finance Committee. Such committees of the Board of Directors shall be formed,
maintained and administered in accordance with the terms of said Section 2.03 of the Governance Agreement, which provisions are incorporated herein and made a part of these Bylaws. All
committees of the Board of Directors not specifically provided for in said Section 2.03 shall be constituted in accordance with Section 2.03(c) of the Governance Agreement.

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