Exhibit 10.21

INFORMATICA CORPORATION

AMENDMENT TO
1999 NON-EMPLOYEE DIRECTOR STOCK INCENTIVE PLAN

        1.   The Board of Directors of Informatica Corporation (the “Company”)
has amended and restated Section 5(b) of the 1999 Non-Employee Director Stock
Incentive Plan (the “Plan”) to provide as follows:               “(b) Date of
Grant and Number of Shares: A Non-Qualified Stock Option to purchase 60,000
Shares (which number reflects each of the Company’s stock splits effected prior
to April 22, 2003) shall be granted automatically (“Initial Grant”) to each
Non-Employee Director elected or appointed to the Board after the Registration
Date upon the date each such Non-Employee Director first becomes a Non-Employee
Director. In addition, immediately following each annual meeting of the
Company’s stockholders, each Non-Employee Director who continues as a
Non-Employee Director following such annual meeting shall be granted
automatically a Non-Qualified Stock Option to purchase 20,000 Shares (which
number reflects each of the Company’s stock splits effected prior to April 22,
2003) (“Subsequent Grant”); provided that no Subsequent Grant shall be made to
any Non-Employee Director who has not served as a Director, as of the time of
such annual meeting, for at least six (6) months. Each such Subsequent Grant
shall be made on the date of the annual stockholders’ meeting in question.”    
    2.   The Board of Directors of the Company has amended and restated
Section 5(c) of the Plan to provide as follows:               “(c) Vesting. Each
Initial Grant shall vest and become exercisable as to one-third (1/3) of the
Shares subject to such Option twelve (12) months after the grant date, and the
remainder of the Initial Grant shall vest in equal monthly installments over the
following 24-month period, such that the Option will be fully exercisable three
(3) years after its date of grant. Each Subsequent Grant shall vest and become
fully exercisable as to all of the Shares subject to such Option twelve
(12) months after the grant date.”