THE MOSAIC COMPANY

Exhibit 10.iii.b

THE MOSAIC COMPANY

NON-QUALIFIED STOCK OPTION AGREEMENT

This NON-QUALIFIED STOCK OPTION AGREEMENT (the “Agreement”) is made this          day of             ,             , by and between The Mosaic Company, a Delaware corporation (the “Company”) and              (the “Participant”).

1. Grant of Option/Termination of Option. The Company hereby grants Participant the option (the “Option”) to purchase all or any part of an aggregate of              shares (the “Shares”) of Common Stock of the Company at the exercise price of $             per share according to the terms and conditions set forth in this Agreement and in The Mosaic Company 2004 Omnibus Stock and Incentive Plan (the “Plan”). The Option will not be treated as an incentive stock option within the meaning of Section 422 of the Internal Revenue Code of 1986, as amended (the “Code”). The Option is issued under the Plan and is subject to its terms and conditions. A copy of the Plan will be furnished upon request of Participant. The Option shall terminate at the close of business ten (10) years from the date hereof.

2. Vesting of Option Rights.

(a) Except as otherwise provided in this Agreement, the Option may be exercised by Participant in accordance with the following schedule:

(b) During the lifetime of Participant, the Option shall be exercisable only by Participant and shall not be assignable or transferable by Participant, other than by will or the laws of descent and distribution. Notwithstanding the foregoing, Participant may transfer the Option to any Family Member (as such term is defined in the General Instructions to Form S-8 (or successor to such Instructions or such Form)), provided, however, that (i) Participant may not receive any consideration for such transfer, (ii) the Family Member must agree in writing not to make any subsequent transfers of the Option other than by will or the laws of the descent and distribution and (iii) the Company receives prior written notice of such transfer.

3. Exercise of Option after Death or Termination of Employment. The Option shall terminate and may no longer be exercised if Participant ceases to be employed by the Company or its affiliates, except that:

(a) If Participant’s employment shall be terminated for any reason, voluntary or involuntary, other than for “Cause” (as defined in Section 3(e)) or Participant’s retirement, death or disability (within the meaning of Section 22(e)(3) of the Code) as provided in Section 3(c) below, Participant may at any time within a period of three (3) months after such termination exercise the Option to the extent the Option was exercisable by Participant on the date of the termination of Participant’s employment.

(b) If Participant’s employment is terminated for Cause, the Option shall be terminated as of the date of the act giving rise to such termination.

(c) If Participant shall die while the Option is still exercisable according to its terms or if employment is terminated because Participant has retired in compliance with the Company’s normal retirement policy at age 65 or older (or pursuant to early retirement with the consent of the Committee) or has become disabled (within the meaning of Section 22(e)(3) of the Code) while in the employ of the Company and Participant shall not have fully exercised the Option, such Option may be exercised at any time within thirty-six (36) months after Participant’s death or date of termination of employment for retirement or disability by Participant, personal representatives or administrators or guardians of Participant, as applicable, or by any person or persons to whom the Option is transferred by will or the applicable laws of descent and distribution, to the extent of the full number of Shares Participant was entitled to purchase under the Option on (i) the earlier of the date of death or termination of employment or (ii) the date of termination for such disability, as applicable.

(d) Notwithstanding the above, in no case may the Option be exercised to any extent by anyone after the termination date of the Option.

(e) “Cause” shall mean (i) the willful and continued failure by Participant substantially to perform his or her duties and obligations (other than any such failure resulting from his or her incapacity due to physical or mental illness), (ii) Participant’s conviction or plea bargain of any felony or gross misdemeanor involving moral turpitude, fraud or misappropriation of funds or (iii) the willful engaging by Participant in misconduct which causes substantial injury to the Company or its Affiliates, its other employees or the employees of its Affiliates or its clients or the clients of its Affiliates, whether monetarily or otherwise. For purposes of this paragraph, no action or failure to act on Participant’s part shall be considered “willful” unless done or omitted to be done, by Participant in bad faith and without reasonable belief that his or her action or omission was in the best interests of the Company.

4. Method of Exercise of Option. Subject to the foregoing, the Option may be exercised in whole or in part from time to time by serving written notice of exercise on the Company at its principal office within the Option period. The notice shall state the number of Shares as to which the Option is being exercised and shall be accompanied by payment of the exercise price. Payment of the exercise price shall be made (i) in cash (including bank check, personal check or money order payable to the Company), (ii) with the approval of the Company (which may be given in its sole discretion), by delivering to the Company for cancellation shares of the Company’s Common Stock already owned by Participant having a Fair Market Value equal to the full exercise price of the Shares being acquired, or (iii) with the approval of the Company (which may be given in its sole discretion), by delivering to the Company a combination thereof.

5. Miscellaneous.

(a) Income Tax Matters.

(i) In order to comply with all applicable federal or state income tax laws or regulations, the Company may take such action as it deems appropriate to ensure that all applicable federal or state payroll, withholding, income or other taxes, which are the sole and absolute responsibility of Participant, are withheld or collected from Participant.

(ii) In accordance with the terms of the Plan, and such rules as may be adopted under the Plan, Participant may elect to satisfy Participant’s federal and state income tax withholding

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obligations arising upon exercise of the Option by (i) delivering cash, check (bank check, certified check or personal check) or money order payable to the Company, (ii) having the Company withhold a portion of the Shares otherwise to be delivered having a Fair Market Value equal to the amount of such taxes, or (iii) delivering to the Company shares of Common Stock already owned by Participant having a Fair Market Value equal to the amount of such taxes. Any such shares already owned by Participant shall have been owned by Participant for no less than six months prior to the date delivered to the Company if such shares were acquired upon the exercise of an option or upon the vesting of restricted stock units or other restricted stock. The Company will not deliver any fractional Shares but will pay, in lieu thereof, the Fair Market Value of such fractional Shares. Participant’s election must be made on or before the date that the amount of tax to be withheld is determined.

(b) Plan Provisions Control. In the event that any provision of the Agreement conflicts with or is inconsistent in any respect with the terms of the Plan, the terms of the Plan shall control. Any term not otherwise defined in this Agreement shall have the meaning ascribed to it in the Plan.

(c) No Rights of Stockholders. Neither Participant, Participant’s legal representative nor a permissible assignee of this Option shall have any of the rights and privileges of a stockholder of the Company with respect to the Shares, unless and until such Shares have been issued in the name of Participant, Participant’s legal representative or permissible assignee, as applicable.

(d) No Right to Employment. The grant of the Option shall not be construed as giving Participant the right to be retained in the employ of the Company or an Affiliate, nor will it affect in any way the right of the Company or an Affiliate to terminate such employment at any time, with or without cause. In addition, the Company or an Affiliate may at any time dismiss Participant from employment free from any liability or any claim under the Plan or the Agreement. Nothing in the Agreement shall confer on any person any legal or equitable right against the Company or any Affiliate, directly or indirectly, or give rise to any cause of action at law or in equity against the Company or an Affiliate. The Option granted hereunder shall not form any part of the wages or salary of Participant for purposes of severance pay or termination indemnities, irrespective of the reason for termination of employment. Under no circumstances shall any person ceasing to be an employee of the Company or any Affiliate be entitled to any compensation for any loss of any right or benefit under the Agreement or Plan which such employee might otherwise have enjoyed but for termination of employment, whether such compensation is claimed by way of damages for wrongful or unfair dismissal, breach of contract or otherwise. By participating in the Plan, Participant shall be deemed to have accepted all the conditions of the Plan and the Agreement and the terms and conditions of any rules and regulations adopted by the Committee and shall be fully bound thereby.

(e) Governing Law. The validity, construction and effect of the Plan and the Agreement, and any rules and regulations relating to the Plan and the Agreement, shall be determined in accordance with the internal laws, and not the law of conflicts, of the State of Delaware. Participant hereby submits to the nonexclusive jurisdiction and venue of the federal or state courts of Delaware to resolve any and all issues that may arise out of or relate to the Plan or the Agreement.

(f) Severability. If any provision of the Agreement is or becomes or is deemed to be invalid, illegal or unenforceable in any jurisdiction or would disqualify the Agreement under any law deemed applicable by the Committee, such provision shall be construed or deemed amended to conform to applicable laws, or if it cannot be so construed or deemed amended without, in the determination of the Committee, materially altering the purpose or intent of the Plan or the Agreement, such provision shall be stricken as to such jurisdiction or the Agreement, and the remainder of the Agreement shall remain in full force and effect.

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(g) No Trust or Fund Created. Participant shall have no right, title, or interest whatsoever in or to any investments that the Company, its Subsidiaries, and/or its Affiliates may make to aid it in meeting its obligations under the Plan. Neither the Plan nor the Agreement shall create or be construed to create a trust or separate fund of any kind or a fiduciary relationship between the Company or any Affiliate and Participant or any other Person.

(h) Headings. Headings are given to the Sections and subsections of the Agreement solely as a convenience to facilitate reference. Such headings shall not be deemed in any way material or relevant to the construction or interpretation of the Agreement or any provision thereof.

(i) Conditions Precedent to Issuance of Shares. Shares shall not be issued pursuant to the exercise of the Option unless such exercise and the issuance and delivery of the applicable Shares pursuant thereto shall comply with all relevant provisions of law, including, without limitation, the Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as amended, the rules and regulations promulgated thereunder, the requirements of any applicable Stock Exchange and the Delaware General Corporation Law. As a condition to the exercise of the Option, the Company may require that the person exercising or paying the purchase price represent and warrant that the Shares are being purchased only for investment and without any present intention to sell or distribute such Shares if, in the opinion of counsel for the Company, such a representation and warranty is required by law.

IN WITNESS WHEREOF, the Company and Participant have executed this Agreement on the date set forth in the first paragraph.

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