Exhibit 10.520

CHIRON CORPORATION FINANCE COMMITTEE CHARTER

ROLE

The
Finance Committee (the "Committee") of the Board of Directors (the "Board") of Chiron Corporation ("Chiron") assists the Board in fulfilling its responsibility for oversight with
respect to Chiron's capital structure, financing and investment strategies and financial management.

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. At least a majority of the members of the Committee shall not be officers or employees of Chiron and shall be free of any
relationship that, in the determination of the Board, would interfere with his or her individual exercise of independent judgment.

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. 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 below 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.

EDUCATION

Chiron
is responsible for providing the Committee with educational resources related to its role and duties and responsibilities, including those with respect to capitalization,
financings, investment strategies 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

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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 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 Finance Committee Charter. 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, consultants, counsel, advisors and experts in carrying out its oversight responsibilities.

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ANNEX A

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



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