DOCUMENT TYPE SC 13G/A
TEXT

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934

Amendment # 1

Name of Issuer: SemGroup Corp
_____________________________________________________
Title of Class
of Securities: Common Stock

CUSIP Number: 81663A105

1) NAME AND I.R.S. IDENTIFICATION NO. OF REPORTING PERSON

Prudential Financial, Inc. 22-3703799

2.) MEMBER OF A GROUP: (a) N/A
(b) N/A

3) SEC USE ONLY:

4) PLACE OF ORGANIZATION: New Jersey

NUMBER OF SHARES BENEFICIALLY OWNED BY REPORTING PERSON WITH:

5) Sole Voting Power: 17,940 See Exhibit A
6) Shared Voting Power: 1,733,171 See Exhibit A
7) Sole Dispositive Power: 17,940 See Exhibit A
8) Shared Dispositive Power: 1,733,171 See Exhibit A

9) AGGREGATE AMOUNT BENEFICIALLY OWNED: 1,751,111 See Exhibit A

10) AGGREGATE AMOUNT IN ROW (9) EXCLUDES SHARES: Not Applicable

11) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9): 2.2 See Exhibit A

12) TYPE OF REPORTING PERSON: HC

ITEM 1(a). NAME OF ISSUER:

SemGroup Corp

ITEM 1(b). ADDRESS OF ISSUER'S EXECUTIVE OFFICES:

TWO WARREN PLACE
6120 SOUTH YALE AVENUE, SUITE 1500
TULSA, OK 74136-4216

ITEM 2(a). NAME OF PERSON FILING:

Prudential Financial, Inc.

ITEM 2(b). ADDRESS OF PRINCIPAL BUSINESS OFFICE:

751 Broad Street
Newark, New Jersey 07102-3777

ITEM 2(c). CITIZENSHIP:

New Jersey

ITEM 2(d). TITLE OF CLASS OF SECURITIES:

Common Stock

ITEM 2(e). CUSIP NUMBER:

81663A105

ITEM 3. The Person filing this statement is a Parent Holding Company as
defined in Section 240.13d-1(b)(1)(ii)(G) of the Securities Exchange
Act of 1934.

ITEM 4. OWNERSHIP:

(a) Number of Shares
Beneficially Owned: 1,751,111
See Exhibit A

(b) Percent of Class: 2.2

(c) Powers                No. Of Shares

   -----------           --------------------

Sole power to vote or    17,940  See Exhibit A
to direct the vote

Shared power to vote or   1,733,171  See Exhibit A
to direct the vote

Sole power to dispose or  17,940 See Exhibit A
to direct disposition

Shared power to dispose   1,733,171  See Exhibit A
or to direct disposition

ITEM 5. OWNERSHIP OF 5% OR LESS OF A CLASS:

Prudential Financial, Inc. through its beneficial ownership of the Item 7 listed entities has ceased to be deemed the beneficial owner of more than 5% of the outstanding Common Stock of this issuer.

ITEM 6. OWNERSHIP OF MORE THAN 5% ON BEHALF OF
ANOTHER PERSON:
Not Applicable

ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE
SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING
REPORTED ON BY THE ULTIMATE PARENT COMPANY:

See Exhibit A

ITEM 8. IDENTIFICATION AND CLASSIFICATION OF
MEMBERS OF THE GROUP:

Not Applicable

ITEM 9. NOTICE OF DISSOLUTION OF GROUP:

Not Applicable

ITEM 10. CERTIFICATION:

By signing below, Prudential Financial, Inc. certifies that, to the best of its
knowledge and belief, the securities referred to above were acquired
and are held in the ordinary course of business and were not acquired
and are not held for the purpose of or with the effect of changing or
influencing the control of the issuer of the securities and were not acquired
and are not held in connection with or as a participant in any transaction
having that purpose or effect.

The filing of this statement should not be construed as an admission that
Prudential Financial, Inc. is, for purposes of Sections 13 or 16 of the Securities
Exchange Act of 1934, the beneficial owner of such shares.

SIGNATURE

After reasonable inquiry and to the best of its knowledge and belief,
Prudential Financial, Inc. certifies that the information set forth in this
statement is true, complete and correct.

PRUDENTIAL FINANCIAL, INC.

By: Richard Baker
Second Vice President

Date: 02/02/2018
As of: 12/31/2017

Exhibit A
--------------

ITEM 4. OWNERSHIP:

Through its parent/subsidiary relationship, Prudential Financial, Inc. may be
deemed the beneficial owner of the same securities as the Item 7 listed
subsidiaries and may have direct or indirect voting and/or investment
discretion over 1,751,111 shares.

These shares were acquired in the ordinary course of business, and not with the
purpose or effect of changing or influencing control of the Issuer.  The filing
of this statement should not be construed as an admission that Prudential
Financial, Inc. is, for the purposes of Sections 13 or 16 of the Securities
Exchange Act of 1934, the beneficial owner of these shares.

ITEM 7. IDENTIFICATION/CLASSIFICATION:

Prudential Financial, Inc. is a Parent Holding Company and the indirect parent
of the following subsidiaries, who are the beneficial owners of the number and
percentage of securities which are the subject of this filing as set forth next
to their names:

Subsidiaries		Number of Shares	Percentage	
The Prudential Insurance Company of America	IC	0	0	
Prudential Retirement Insurance and Annuity Company	IC	0	0	
Jennison Associates LLC	IA	1,743,178	2.22	
PGIM, Inc.	IA	0	0	
Quantitative Management Associates LLC	IA	7,933	0.01