Exhibit 10.516

CHIRON CORPORATION COMPENSATION COMMITTEE CHARTER    ROLE

The Compensation Committee (the "Committee") of the Board of Directors (the "Board") of Chiron Corporation ("Chiron") assists the Board in fulfilling its
responsibility for oversight of the compensation plans and programs of Chiron generally. In addition, the Committee approves the compensation of the executive officers of Chiron and makes
recommendations to the Board regarding the compensation of the members of Chiron's Board for services as directors.

The
chairperson of the Committee, acting in consultation with all committee members that are not otherwise affected by the issue or interest under consideration, and in consultation with
such other directors, representatives of management, counsel or other advisors as the chairperson may deem appropriate, may determine from time to time the scope of the Committee's authority under
this charter.

MEMBERSHIP AND STRUCTURE

The Committee shall consist of at least three directors. A member shall not be an officer or employee of Chiron, each member shall be free of any relationship
that, in the determination of the Board, would interfere with his or her individual exercise of independent judgment and each member shall otherwise be "independent" and qualified to serve as a member
of the Committee under applicable law and under the rules of the Nasdaq Stock Market, Inc. The Committee shall review at least annually, and upon the occurrence of any significant change, the
qualification and independence of its members, and shall report the result of this review to the full Board.

Subject
to the requirements described above with respect to Committee membership, members of the Committee shall be appointed by the Board in accordance with the Governance Agreement,
dated as of November 20, 1994, between Chiron and Novartis AG, as amended (as it may be further amended
from time to time, the "Governance Agreement"). Committee members shall serve at the pleasure of the Board. The chairperson shall be appointed by the full Board.

The
Committee shall meet in person or telephonically at least two times a year or more frequently when deemed necessary or desirable by the Committee or its chairperson, at such times
and places as the Committee determines.

COMMUNICATIONS/REPORTING

The Committee may invite such members of management to its meetings as it may deem desirable, consistent with the maintenance of confidentiality of compensation
discussions. The Committee shall meet in private executive session at least annually to consider the performance and compensation of the Chief Executive Officer ("CEO"). The Committee shall cause to
be prepared, reviewed and approved the annual report on executive compensation to be included in Chiron's proxy statement. The Committee shall perform or cause to be performed and approved by the
Committee annually an evaluation of the performance of the Committee of its role under this charter, including the duties and responsibilities set forth in Annex A. The evaluation shall include
consideration of possible amendments to this charter, including the duties and responsibilities set forth in Annex A. The performance evaluation may be conducted in such manner as the Committee deems
appropriate, and the result and recommendations shall be reported to the Board by the chairperson or any other member of the Committee. The chairperson shall report in a timely manner on Committee
activities to the full Board.

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EDUCATION

Chiron is responsible for providing the Committee with educational resources related to its role and duties and responsibilities, including executive officer and
director compensation practices, employee benefit and compensation plan requirements and practices and any other material as may be requested by the Committee.

AUTHORITY

In discharging its oversight role, duties and responsibilities, the Committee is empowered to cause and direct the investigation of any matter within its role,
with full power to cause independent counsel or other experts or advisors to be retained for this purpose. The Committee may require any officer or employee of Chiron or Chiron's outside lawyers to
attend a meeting of the Committee or to meet with any member of or consultants to the Committee and to provide any information requested by the Committee or its member or consultants. The Committee
shall have the full authority of the Board to discharge its duties and responsibilities, including the authority to select, retain, terminate and approve the compensation and other terms of engagement
of independent compensation consultants, counsel, accountants or other experts or advisors as the Committee deems appropriate in its discretion, without seeking approval of the Board or management.
The Committee may, in its discretion, delegate all or a portion of its duties and responsibilities to a subcommittee of the Committee. The Committee shall also have the resources that it deems
necessary to discharge its duties and responsibilities.

KEY DUTIES AND RESPONSIBILITIES

The key duties and responsibilities of the Committee in carrying out its role are delineated in Annex A to the Compensation Committee Charter. In addition, the
Committee may be subject to duties under the Governance Agreement. Annex A will be reviewed annually, and updated if necessary, to reflect changes in regulatory requirements, authoritative guidance
and evolving oversight practices. As the compendium of Committee duties and responsibilities, Annex A will be considered to be incorporated in, and a part of, this charter.

The
Committee may rely on the expertise and knowledge of management, compensation consultants, counsel, advisors and experts in carrying out its oversight responsibilities. Management of
Chiron is responsible for the development and administration of Chiron's compensation and benefit plans and programs. It is not the duty of the Committee to plan or conduct investigations, to assure
the adequacy or effectiveness of Chiron's compensation plans and programs or to assure compliance with laws and regulations or with company's policies, procedures and controls.

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ANNEX A

The following are the key duties and responsibilities of the Committee:



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