Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MACK RICHARD L
  2. Issuer Name and Ticker or Trading Symbol
MOSAIC CO [MOS]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, Chief Financial Officer
(Last)
(First)
(Middle)
C/O THE MOSAIC COMPANY, 3033 CAMPUS DRIVE, SUITE E490
3. Date of Earliest Transaction (Month/Day/Year)
03/03/2016
(Street)

PLYMOUTH, MN 55441
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock               85,024 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (Right to Buy) $ 15.45               (1) 08/04/2016 Common Stock 47,319   47,319 D  
Stock Option (Right to Buy) $ 40.03               (1) 08/02/2017 Common Stock 19,368   19,368 D  
Stock Option (Right to Buy) $ 127.21               (1) 07/31/2018 Common Stock 5,486   5,486 D  
Stock Option (Right to Buy) $ 52.72               (1) 07/27/2019 Common Stock 10,216   10,216 D  
Stock Option (Right to Buy) $ 44.93               (1) 07/27/2020 Common Stock 15,194   15,194 D  
Stock Option (Right to Buy) $ 70.62               (1) 07/21/2021 Common Stock 10,767   10,767 D  
Stock Option (Right to Buy) $ 57.62               (1) 07/19/2022 Common Stock 17,483   17,483 D  
Restricted Stock Units $ 0 (2)             07/18/2016   (3) Common Stock 7,403   7,403 D  
Stock Option (Right to Buy) $ 54.03               (4) 07/18/2023 Common Stock 18,939   18,939 D  
Restricted Stock Units $ 0 (2)             03/07/2017   (3) Common Stock 8,043   8,043 D  
Stock Option (Right to Buy) $ 49.73               (5) 03/07/2024 Common Stock 21,288   21,288 D  
Stock Option (Right to Buy) $ 50.43               (6) 03/05/2025 Common Stock 24,249   24,249 D  
Restricted Stock Units $ 0 (2)               (7)   (3) Common Stock 21,949   21,949 D  
Stock Option (Right to Buy) $ 28.49 03/03/2016   A   48,202     (8) 03/03/2026 Common Stock 48,202 $ 0 48,202 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MACK RICHARD L
C/O THE MOSAIC COMPANY
3033 CAMPUS DRIVE, SUITE E490
PLYMOUTH, MN 55441
      EVP, Chief Financial Officer  

Signatures

 /s/ Mark J. Isaacson, Attorney-in-Fact for Richard L. Mack   03/03/2016
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) This Stock Option is 100% exercisable.
(2) One-for-One
(3) Not Applicable
(4) Grant Date 07/18/2013; option becomes exercisable in three equal installments commencing on the first anniversary of the grant date and on each anniversary thereafter.
(5) Grant Date 03/07/2014; option becomes exercisable in three equal installments commencing on the first anniversary of the grant date and on each anniversary thereafter.
(6) Grant Date 03/05/2015; option becomes exercisable in three equal installments commencing on the first anniversary of the grant date and on each anniversary thereafter.
(7) Grant Date 5/14/2015; restricted stock units vest in three equal installments commencing on the first anniversary of the grant date and on each anniversary thereafter.
(8) Grant Date 03/03/2016; option becomes exercisable in three equal installments commencing on the first anniversary of the grant date and on each anniversary thereafter.

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