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
                                                                                  
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
                      
1. Name and Address of Reporting Person * Sammann Derek 2. Issuer Name and Ticker or Trading Symbol CME GROUP INC. [ CME ] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable)_____ Director                    _____ 10% Owner
__X__ Officer (give title below)    _____ Other (specify below)
Sr MD Gl Hd Commodity & Option
(Last)         (First)         (Middle)
20 S. WACKER DRIVE
3. Date of Earliest Transaction (MM/DD/YYYY)
2/26/2021
(Street)
CHICAGO, IL 60606
(City)       (State)       (Zip)
4. If Amendment, Date Original Filed (MM/DD/YYYY)
 
6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Trans. Date 2A. Deemed Execution Date, if any 3. Trans. 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 Class A  2/26/2021    S    3175  D $198.99 (1) 17704  I  by Spouse 
Common Stock Class A  2/26/2021    S    4160  D $199.19  17651  I  by Trust 
Common Stock Class A                 9515  D   
Common Stock Class A                 931  I  by Children (2)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Trans. Date 3A. Deemed Execution Date, if any 4. Trans. 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 7. Title and Amount of Securities Underlying Derivative Security
(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

Explanation of Responses:
(1)  On February 26, 2021, the Trust of Mr. Sammann's spouse sold an aggregate of 3,175 shares of CME Group Class A common stock. For reporting purposes, the sale prices within $1 range have been aggregated and the weighted average has been reported. The price range was $198.91 to $199.03. The Company maintains a record of the transaction and copies will be provided upon request.
(2)  This transaction represented a gift of securities from the reporting person to his children, one of whom shares reporting person's household. The reporting person disclaims beneficial ownership of the shares held by his children, and this report shall not be deemed as an admission that the reporting person is the beneficial owner of his children's shares for purposes of Section 16 or for any other purpose.

Reporting Owners
Reporting Owner Name / Address
Relationships
Director 10% Owner Officer Other
Sammann Derek
20 S. WACKER DRIVE
CHICAGO, IL 60606


Sr MD Gl Hd Commodity & Option

Signatures
By: Margaret Austin Wright For: Derek Louis Sammann 3/2/2021
**Signature of Reporting Person Date