Buffalo Investor I SC 13D/A SemGroup Corp

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

SEMGROUP CORPORATION

(Name of Issuer)

Class A Common Stock

(Title of Class of Securities)

81663A105

(CUSIP Number)

David Lieberman, Esq.

Simpson Thacher & Bartlett LLP

425 Lexington Avenue

New York, New York 10017

(212)455-2000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 16, 2019

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.   ☒

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS BUFFALO INVESTOR I, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 2,294,805
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 2,294,805
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,294,805
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) PN

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS BUFFALO INVESTOR I GP LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 2,294,805
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 2,294,805
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,294,805
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) OO

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS BUFFALO HOLDING I LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 2,294,805
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 2,294,805
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,294,805
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) OO

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS ALINDA INFRASTRUCTURE FUND II, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 2,294,805
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 2,294,805
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,294,805
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) PN

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS ALINDA GP II, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 2,294,805
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 2,294,805
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,294,805
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) PN

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS ALINDA GP OF GP II LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH			7	SOLE VOTING POWER 2,294,805
			8	SHARED VOTING POWER 0
		��	9	SOLE DISPOSITIVE POWER 2,294,805
			10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,294,805
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) OO

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS BUFFALO INVESTOR II, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 359,606
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 359,606
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 359,606
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0.5%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) PN

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS BUFFALO INVESTOR II GP, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 359,606
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 359,606
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 359,606
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0.5%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) OO

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS BUFFALO HOLDING II LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 359,606
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 359,606
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 359,606
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0.5%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) OO

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS ALINDA PARALLEL FUND GP II, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Cayman Islands, British West Indies
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 359,606
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 359,606
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 359,606
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0.5%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) PN

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS ALINDA PARALLEL FUND GP II, LTD.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION Cayman Islands, British West Indies
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 359,606
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 359,606
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 359,606
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0.5%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO

CUSIP No. 81663A105

1	NAMES OF REPORTING PERSONS CHRISTOPHER W. BEALE
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a)  ☐        (b)  ☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E)  ☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION United States
NUMBER OF SHARES BENEFICIALLY   OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 2,654,411
		8	SHARED VOTING POWER 0
		9	SOLE DISPOSITIVE POWER 2,654,411
		10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,654,411
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)  ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 3.4%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) IN

This Amendment No. 1 (“Amendment No. 1”) to Schedule 13D relates to the Class A Common Stock, par value $0.01 per share (“Class A Common Stock”) of SemGroup Corporation, a Delaware corporation (the “Issuer”) and amends the initial statement on Schedule 13D filed on May 13, 2019 (as amended, the “Schedule13D”). Capitalized terms used but not defined in this Amendment No. 1 shall have the same meanings ascribed to them in the Schedule 13D.

Item 5. Interest in Securities of the Issuer

Items 5(a) – (c) of the Schedule 13D are hereby amended and restated as follows:

(a) and (b) The percentage of beneficial ownership in this Schedule 13D is based on an aggregate of 78,686,816 shares of Class A Common Stock issued and outstanding as of September 13, 2019, as set forth in the Agreement and Plan of Merger, dated as of September 15, 2019, attached as Exhibit 2.1 to the Current Report on Form8-K filed by the Issuer with the Securities and Exchange Commission on September 16, 2019.

The aggregate number and percentage of shares of Class A Common Stock beneficially owned by each Reporting Person and, for each Reporting Person, the number of shares as to which there is sole power to vote or to direct the vote, shared power to vote or to direct the vote, sole power to dispose or to direct the disposition, or shared power to dispose or to direct the disposition are set forth on rows 7 through 11 and row 13 of the cover pages of this Schedule 13D and are incorporated herein by reference.

As of the date hereof, Buffalo Investor I, L.P. directly holds 2,294,805 shares of Class A Common Stock, and Buffalo Investor II, L.P. directly holds 359,606 shares of Class A Common Stock. Mr. Beale is the managing member of Alinda GP of GP II LLC, which is the general partner of Alinda GP II, L.P., which is the sole member of Buffalo Investor I GP LLC, which is the general partner of Buffalo Investor I, L.P. Mr. Beale is a Director of Alinda Parallel Fund GP II, Ltd., which is the general partner of Alinda Parallel Fund GP II, L.P., which is the sole member of Buffalo Investor II GP, LLC, which is the general partner of Buffalo Investor II, L.P.

To the best knowledge of the Reporting Persons, none of the persons listed in Annex A beneficially owns any shares of Class A Common Stock.

(c)    Except as set forth on Schedule 1 attached hereto, none of the Reporting Persons, or, to the best knowledge of the Reporting Persons, any of the persons listed on Annex A, has effected any transactions in the Class A Common Stock during the past 60 days.

Item 5(e) of the Schedule 13D is hereby amended and restated as follows:

As of September 18, 2019, the Reporting Persons ceased to beneficially own more than five percent of the outstanding shares of Class A Common Stock.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

September 18, 2019

BUFFALO INVESTOR II, L.P. By: BUFFALO INVESTOR II GP, LLC, its general partner
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
BUFFALO INVESTOR II GP, LLC
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
BUFFALO HOLDING II LLC
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
ALINDA PARALLEL FUND GP II, L.P. By: ALINDA PARALLEL FUND GP II, LTD., its general partner
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	Director
BUFFALO INVESTOR I, L.P. By: BUFFALO INVESTOR I GP, LLC, its general partner
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President

BUFFALO INVESTOR I GP, LLC
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
BUFFALO HOLDING I LLC
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
ALINDA INFRASTRUCTURE FUND II, L.P. By: ALINDA GP II, L.P., its general partner
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
ALINDA GP II, L.P. By: ALINDA GP OF GP II LLC, its general partner
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
ALINDA GP OF GP II LLC
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President
ALINDA PARALLEL FUND GP II, LTD.
By:	/s/ Christopher W. Beale
Name:	Christopher W. Beale
Title:	President

/s/ Christopher W. Beale

Christopher W. Beale

SCHEDULE 1

As of September 18, 2019, the below reflects the transactions in Class A Common Stock effected by the Reporting Persons during the past 60 days. All transactions occurred in the open market.

Date	Class A Common Stock Sold		Weighted Average Price per Share		Seller
9/16/2019		2,821,204	$	16.61	Buffalo Investor I, L.P.
9/16/2019		2,821,204	$	16.61	Buffalo Investor II, L.P.
9/17/2019		1,042,575	$	16.47	Buffalo Investor I, L.P.
9/17/2019		1,042,575	$	16.47	Buffalo Investor II, L.P.
9/18/2019		1,187,545	$	16.56	Buffalo Investor I, L.P.
9/18/2019		814,386	$	16.56	Buffalo Investor II, L.P.