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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OMB Number: 3235-0287
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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 *

SELL THOMAS D	2. Issuer Name and Ticker or Trading Symbol

SemGroup Corp [ SEMG ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable)

_____ Director                      _____ 10% Owner
__ X __ Officer (give title below)      _____ Other (specify below)
VP, Controller & CAO	
(Last)          (First)          (Middle)

6120 SOUTH YALE AVE., SUITE 1500	3. Date of Earliest Transaction (MM/DD/YYYY)

3/1/2018		
(Street)

TULSA, OK 74136
(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  	3/1/2018  	 	A	  	7373  	A	$0.00  	19992  	D  	 	

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:	

Reporting Owners	
Reporting Owner Name / Address	Relationships	
	Director	10% Owner	Officer	Other	
SELL THOMAS D
6120 SOUTH YALE AVE.
SUITE 1500
TULSA, OK 74136			VP, Controller & CAO		

Signatures		
William Gault, Power of Attorney for Thomas D. Sell		3/5/2018	
** Signature of Reporting Person		Date

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.	
*	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).	
Note:	File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.	
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.	

POWER OF ATTORNEY

        The undersigned hereby makes, constitutes and appoints each of Susan S.
Lindberg,
Robert N. Fitzgerald and William Gault, signing singly, as the undersigned's
true and lawful
attorney-in-fact, with full power and authority as hereinafter described on
behalf of and in the
name, place and stead of the undersigned to:
        (1)     prepare, execute, acknowledge in the undersigned's name and on the
undersigned's behalf, and submit to the U.S. Securities and Exchange Commission
(the "SEC") a
Form ID, including any amendments thereto, and any other documents necessary or
appropriate
to obtain codes and passwords enabling the undersigned to make electronic
filings with the SEC
of reports required by Section 16 of the Securities Exchange Act of 1934 and the
rules and
regulations promulgated thereunder, as amended from time to time (the "Exchange
Act"), or any
rule or regulation of the SEC;
        (2)     prepare, execute, acknowledge, deliver and file Forms 3, 4 and 5 or such
other
forms, including any amendments thereto, as may be required by Section 16 of the
Exchange Act
with respect to the securities of SemGroup Corporation, a Delaware corporation
(the
"Company"), with the SEC and the Company;
        (3)     seek or obtain, as the undersigned's representative and on the
undersigned's
behalf, information on transactions in the Company's securities from any third
party, including
brokers, employee benefit plan administrators and trustees, and the undersigned
hereby
authorizes any such person to release any such information to the undersigned
and approves and
ratifies any such release of information; and
        (4)     perform any and all other acts which in the discretion of such
attorney-in-fact are
determined to be necessary or desirable for and on behalf of the undersigned in
connection with
the foregoing.
The undersigned acknowledges that:
        (1)     this Power of Attorney authorizes, but does not require, each such
attorney-in-fact
to act in his or her discretion on information provided to such attorney-in-fact
without
independent verification of such information;
        (2)     any documents prepared and/or executed by each such attorney-in-fact on
behalf
of the undersigned pursuant to this Power of Attorney will be in such form and
will contain such
information and disclosure as such attorney-in-fact, in his or her discretion,
deems necessary or
desirable;

        (3)     neither the Company nor such attorneys-in-fact assume(s) (i) any liability
for the
undersigned's responsibility to comply with the requirements of the Exchange
Act, (ii) any
liability of the undersigned for any failure to comply with such requirements,
or (iii) any
obligation or liability of the undersigned for profit disgorgement under Section
16(b) of the
Exchange Act; and
        (4)     this Power of Attorney does not relieve the undersigned from responsibility
for
compliance with the undersigned's obligations under the Exchange Act, including
without
limitation the reporting requirements under Section 16 of the Exchange Act.
        The undersigned hereby gives and grants to each such attorney-in-fact full
power and
authority to do and perform all and every act and thing whatsoever requisite,
necessary or
appropriate to be done in and about the foregoing matters as fully to all
intents and purposes as
the undersigned might or could do if present, hereby ratifying all that such
attorney-in-fact of, for
and on behalf of the undersigned, shall lawfully do or cause to be done by
virtue of this Power of
Attorney.
        This Power of Attorney shall remain in full force and effect until revoked by
the
undersigned in a signed writing delivered to such attorneys-in-fact.
        IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 26th day of June, 2017.
/s/ Thomas D. Sell
Thomas D. Sell

STATE OF OKLAHOMA       )
                                ) ss.
COUNTY OF TULSA )

On this 26th day of June, in the year 2017, before me, the undersigned, a Notary
Public in and
for said state, personally appeared Thomas D. Sell, personally known to me or
proved to me on
the basis of satisfactory evidence to be the person whose name is subscribed to
the within
instrument and acknowledged to me that he/she executed the same in his/her
capacity, and that
by his/her signature on the instrument, the person or the entity upon behalf of
which the person
acted, executed the instrument.

(SEAL)

                                                /s/ Elayna M. Conner
                                                Notary Public

                                                My Commission Expires: 2/22/2018

Exhibit 24