[FORM OF PERFORMANCE-BASED STOCK OPTION AGREEMENT] CALLIDUS SOFTWARE, INC. 2003STOCK INCENTIVE PLAN STOCK OPTION AGREEMENT

Exhibit 10.28

[FORM OF PERFORMANCE-BASED STOCK OPTION AGREEMENT]

CALLIDUS SOFTWARE, INC.

2003 STOCK INCENTIVE PLAN

STOCK OPTION AGREEMENT

      Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Option Agreement.

I.     NOTICE OF STOCK OPTION GRANT

      [Name]

      [Address]

      The undersigned Optionee has been granted an Option to purchase Common Stock of the Company, subject to the terms and conditions of the Plan and this Option Agreement, as follows:

      This Option shall be exercisable, in whole or in part, according to the following vesting schedule:

      Grants will vest 100% three years from the date of grant. Vesting will accelerate in accordance with the table below at the end of any 22 consecutive trading periods (i.e. on the 23^rd day) in which:

      (i) The average closing price during that 22 consecutive day period is equal to or exceeds the Target Stock Price listed below: and

      (ii) The closing stock price for at least 15 trading days within the 22-day consecutive period is equal to or exceeds the Target Stock Price.

Target Stock Price $5/share - 20% cumulatively vested

Target Stock Price $8/share - 40% cumulatively vested

Target Stock Price $11/share - 60% cumulatively vested

Target Stock Price $13/share - 80% cumulatively vested

Target Stock price $16/share – 100% cumulatively vested

      Termination Period:

      This Option shall be exercisable for 90 days after Optionee ceases to be a Service Provider. Upon Optionee’s death or disability, this Option may be exercised for such longer period as provided in the Plan. In no event may Optionee exercise this Option after the Term/Expiration Date as provided above.

II.    AGREEMENT

      1.  Grant of Option. The Plan Administrator of the Company hereby grants to the Optionee named in the Notice of Grant (the “Optionee”), an option (the “Option”) to purchase the number of Shares set forth in the Notice of Grant, at the exercise price per Share set forth in the Notice of Grant (the “Exercise Price”), and subject to the terms and conditions of the Plan, which is incorporated herein by reference. Subject to Section 15(c) of the Plan, in the event of a conflict between the terms and conditions of the Plan and this Option Agreement, the terms and conditions of the Plan shall prevail.

      2.  Exercise of Option.

           (a) Right to Exercise. This Option shall be exercisable during its term in accordance with the Vesting Schedule set out in the Notice of Grant and with the applicable provisions of the Plan and this Option Agreement.

           (b) Method of Exercise. This Option shall be exercisable by delivery of an exercise notice in the form attached as Exhibit A (the “Exercise Notice”) which shall state the election to exercise the Option, the number of Shares with respect to which the Option is being exercised, and such other representations and agreements as may be required by the Company. The Exercise Notice shall be accompanied by payment of the aggregate Exercise Price as to all Exercised Shares. This Option shall be deemed to be exercised upon receipt by the Company of such fully executed Exercise Notice accompanied by the aggregate Exercise Price. The Administrator shall require payment of any amount the Company may determine to be necessary to withhold for taxes as a result of the exercise of an award. In the absence of any other

arrangement, Optionee agrees that the Company shall be entitled to withhold from any payments to be made by the Company to Optionee an amount equal to such withholding obligations.

      No Shares shall be issued pursuant to the exercise of an Option unless such issuance and such exercise complies with Applicable laws. Assuming such compliance, for income tax purposes the Shares shall be considered transferred to the Optionee on the date on which the Option is exercised with respect to such Shares.

      3. Lock-Up Period. Optionee hereby agrees that, if so requested by the Company or any representative of the underwriters (the “Managing Underwriter”) in connection with any registration of the offering of any securities of the Company under the Securities Act, Optionee shall not sell or otherwise transfer any Shares or other securities of the Company during the 180-day period (or such other period as may be requested in writing by the Managing Underwriter and agreed to in writing by the Company) (the “Market Standoff Period”) following the effective date of a registration statement of the Company filed under the Securities Act. Such restriction shall apply only to the first registration statement of the Company to become effective under the Securities Act that includes securities to be sold on behalf of the Company to the public in an underwritten public offering under the Securities Act. The Company may impose stop-transfer instructions with respect to securities subject to the foregoing restrictions until the end of such Market Standoff Period.

      4. Method of Payment. Payment of the aggregate Exercise Price shall be by any of the following, or a combination thereof, at the election of the Optionee:

           (a) cash or check;

           (b) consideration received by the Company under a formal cashless exercise program adopted by the Company in connection with the Plan; or

           (c) surrender of other Shares which, (i) in the case of Shares acquired upon exercise of an option, have been owned by the Optionee for more than six months on the date of surrender, and (ii) have a Fair Market Value on the date of surrender equal to the aggregate Exercise Price of the Exercised Shares.

      5.  Restrictions on Exercise. This Option may not be exercised until such time as the Plan has been approved by the stockholders of the Company, or if the issuance of such Shares upon such exercise or the method of payment of consideration for such shares would constitute a violation of any Applicable Law.

      6. Non-Transferability of Option. This Option may not be transferred in any manner otherwise than by will or by the laws of descent or distribution and may be exercised during the lifetime of Optionee only by Optionee. The terms of the Plan and this Option Agreement shall be binding upon the executors, administrators, heirs, successors and assigns of the Optionee.

      7.  Term of Option. This Option may be exercised only within the term set out in the Notice of Grant, and may be exercised during such term only in accordance with the Plan and the terms of this Option.

      8.  Entire Agreement Governing Law. The Plan is incorporated herein by reference. The Plan and this Option Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and Optionee with respect to the subject matter hereof, and may not be modified adversely to the Optionee’s interest except by means of a writing signed by the Company and Optionee. This agreement is governed by the internal substantive laws but not the choice of law rules of the State of California.

      9.  No Guarantee of Continued Service. OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED ONLY BY CONTINUING AS A SERVICE PROVIDER AT THE WILL OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS OPTION OR ACQUIRING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS A SERVICE PROVIDER FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT INTERFERE IN ANY WAY WITH OPTIONEE’S RIGHT OR THE COMPANY’S RIGHT TO TERMINATE OPTIONEE’S RELATIONSHIP AS A SERVICE PROVIDER AT ANY TIME, WITH OR WITHOUT CAUSE.

      Optionee acknowledges receipt of a copy of the Plan and represents that he or she is familiar with the terms and provisions thereof, and hereby accepts this Option subject to all of the terms and provisions thereof Optionee has reviewed the Plan and this Option in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Option and fully understands all provisions of the Option. Optionee hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan or this Option. Optionee further agrees to notify the Company upon any change in the residence address indicated below.