TransAtlantic Petroleum (TAT) SC 13D/A Transatlantic Petroleum LTD.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities

Exchange Act of 1934

(Amendment No. 18)*

TransAtlantic Petroleum Ltd.

(Name of Issuer)

Common Shares, no par value

(Title of Class of Securities)

G89982113

(CUSIP Number)

Dalea Management, LLC

16803 Dallas Parkway Suite 300

Addison, Texas 75001

Attention: Christine Stroud

(972) 590-9879

(Name, Address and Telephone Number of Person Authorized to

Receive Notices and Communications)

November 15, 2017

(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 Rule 13d-1(e), 13d-1(f) or 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 (the “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 theNotes).

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Dalea Partners, LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED            ☐ PURSUANT TO ITEMS 2(d) or 2(e)
6	CITIZENSHIP OR PLACE OF ORGANIZATION Oklahoma
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER -0-
		8	SHARED VOTING POWER 13,126,887**
		9	SOLE DISPOSITIVE POWER -0-
		10	SHARED DISPOSITIVE POWER 13,126,887**
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 13,126,887**
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 25.1%**
14	TYPE OF REPORTING PERSON PN

*See Item 3.

** While the above figures include all of the 1,921,668 common shares into which Dalea Partners’ Series A Preferred Shares are convertible, please see Item 3 with respect to the limitation on such conversion pursuant to the Mitchell Beneficial Ownership Cap.

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Dalea Management, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED            ☐ PURSUANT TO ITEMS 2(d) or 2(e)
6	CITIZENSHIP OR PLACE OF ORGANIZATION Oklahoma
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER -0-
		8	SHARED VOTING POWER 13,126,887**
		9	SOLE DISPOSITIVE POWER -0-
		10	SHARED DISPOSITIVE POWER 13,126,887**
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 13,126,887**
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 25.1%**
14	TYPE OF REPORTING PERSON CO

*See Item 3.

** While the above figures include all of the 1,921,668 common shares into which Dalea Partners’ Series A Preferred Shares are convertible, please see Item 3 with respect to the limitation on such conversion pursuant to the Mitchell Beneficial Ownership Cap.

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Longfellow Energy, LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED            ☐ PURSUANT TO ITEMS 2(d) or 2(e)
6	CITIZENSHIP OR PLACE OF ORGANIZATION Texas
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER -0-
		8	SHARED VOTING POWER 13,337,903**
		9	SOLE DISPOSITIVE POWER -0-
		10	SHARED DISPOSITIVE POWER 13,337,903**
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 13,337,903**
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 22.3%**
14	TYPE OF REPORTING PERSON PN

*See Item 3.

** While the above figures include all of the 9,379,570 common shares into which Longfellow’s Series A Preferred Shares are convertible, please see Item 3 with respect to the limitation on such conversion pursuant to the Mitchell Beneficial Ownership Cap.

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Deut 8, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED            ☐ PURSUANT TO ITEMS 2(d) or 2(e)
6	CITIZENSHIP OR PLACE OF ORGANIZATION Texas
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER -0-
		8	SHARED VOTING POWER 13,337,903**
		9	SOLE DISPOSITIVE POWER -0-
		10	SHARED DISPOSITIVE POWER 13,337,903**
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 13,337,903**
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 22.3%**
14	TYPE OF REPORTING PERSON CO

*See Item 3.

** While the above figures include all of the 9,379,570 common shares into which Longfellow’s Series A Preferred Shares are convertible, please see Item 3 with respect to the limitation on such conversion pursuant to the Mitchell Beneficial Ownership Cap.

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Pinon Foundation
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED            ☐ PURSUANT TO ITEMS 2(d) or 2(e)
6	CITIZENSHIP OR PLACE OF ORGANIZATION Oklahoma
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER -0-
		8	SHARED VOTING POWER 1,561,797
		9	SOLE DISPOSITIVE POWER -0-
		10	SHARED DISPOSITIVE POWER 1,561,797
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,561,797
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 3.1%
14	TYPE OF REPORTING PERSON PN

*See Item 3.

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) N. Malone Mitchell, 3rd
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX 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 578,937
		8	SHARED VOTING POWER 28,789,338
		9	SOLE DISPOSITIVE POWER 578,937
		10	SHARED DISPOSITIVE POWER 28,789,338
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 29,368,275**
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 47.4%**
14	TYPE OF REPORTING PERSON IN

*See Item 3.

** Please see Item 3 re: the Mitchell Beneficial Ownership Cap.

SCHEDULE 13D

CUSIP No. G89982113

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Amy Mitchell
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)  ☐ (b)  ☑
3	SEC USE ONLY
4	SOURCE OF FUNDS OO*
5	CHECK BOX 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 25,000
		8	SHARED VOTING POWER 28,789,338
		9	SOLE DISPOSITIVE POWER 25,000
		10	SHARED DISPOSITIVE POWER 28,789,338
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 28,814,338**
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES    ☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 46.8%**
14	TYPE OF REPORTING PERSON IN

*See Item 3.

** Please see Item 3 re: the Mitchell Beneficial Ownership Cap.

AMENDMENT NO. 18 TO SCHEDULE 13D

This Amendment No. 18 to Schedule 13D (this “Eighteenth Amendment”) amends and supplements the Schedule 13D originally filed on April 17, 2008, as amended by Amendment No. 1 on June 25, 2008, Amendment No. 2 on August 28, 2008, Amendment No. 3 on September 29, 2008, Amendment No. 4 on December 30, 2008, Amendment No. 5 on July 2, 2009, Amendment No. 6 on December 3, 2009, Amendment No. 7 on September 13, 2010, Amendment No. 8 on May 17, 2011, Amendment No. 9 on March 23, 2012, Amendment No. 10 on January 10, 2014, Amendment No. 11 on January 14, 2015, Amendment No. 12 on May 5, 2015, Amendment No. 13 on August 28, 2015, Amendment No. 14 on April 13, 2016, Amendment No. 15 on July 12, 2016, Amendment No. 16 on December 1, 2016, and Amendment No 17 on April 20, 2017 (collectively, the “Schedule 13D”). Unless otherwise indicated, all capitalized terms used but not defined herein shall have the same meaning ascribed to them in the Schedule 13D.

This Eighteenth Amendment is being filed to make updates and amendments to the Schedule 13D as follows:

Item 1. Security and Issuer

There are no changes to the Item 1 information previously filed.

Item 2. Identity and Background

Item 2 is hereby amended and supplemented by deleting Pinon Foundation from the definition of “Reporting Persons.”

Item 3. Source and Amount of Funds or Other Consideration

Item 3 is hereby amended and supplemented by adding the following sentences thereto:

On November 15, 2017, Longfellow acquired an aggregate 205,000 shares of Issuer’s Series A Preferred Shares from Pinon Foundation at a total cash purchase price of $10,250,000.00. The shares were purchased by Longfellow with cash on hand.

Item 4. Purpose of the Transaction

There are no changes to the Item 4 information previously filed.

Item 5. Interest in Securities of the Issuer

Item 5 is hereby amended and restated to read in its entirety as follows:

(a) Amount beneficially owned

(i) Dalea Partners beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Dalea Partners cover page of this Eighteenth Amendment.

(ii) Dalea Management beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Dalea Management cover page of this Eighteenth Amendment.

(iii) Longfellow beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Longfellow cover page of this Eighteenth Amendment.

(iv) Deut 8 beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Deut 8 cover page of this Eighteenth Amendment.

(v) Pinon Foundation beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Pinon Foundation cover page of this Eighteenth Amendment.

(vi) Mitchell beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Mitchell cover page of this Eighteenth Amendment.

(vii) Amy Mitchell beneficially owns the aggregate number and percentage of the Issuer’s common shares as stated in Rows 11 and 13 of the Amy Mitchell cover page of this Eighteenth Amendment.

(b) Power to Vote/ Power to Dispose:

(i) Dalea Partners shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Dalea Partners cover page of this Eighteenth Amendment.

(ii) Dalea Management shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Dalea Management cover page of this Eighteenth Amendment.

(iii) Longfellow shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Longfellow cover page of this Eighteenth Amendment.

(iv) Deut 8 shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Deut 8 cover page of this Eighteenth Amendment.

(v) Pinon Foundation shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Pinon Foundation cover page of this Eighteenth Amendment

(vi) Mitchell possesses the sole power to vote and the sole power to dispose the amount of the Issuer’s common shares listed in Rows 7 and 9 of the Mitchell cover page of this Eighteenth Amendment. Mitchell shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Mitchell cover page of this Eighteenth Amendment.

(vii) Amy Mitchell possesses the sole power to vote and the sole power to dispose the amount of the Issuer’s common shares listed in Rows 7 and 9 of the Amy Mitchell cover page of this Eighteenth Amendment. Amy Mitchell shares the power to vote and the power to dispose the amount of the Issuer’s common shares listed in Rows 8 and 10 of the Amy Mitchell cover page of this Eighteenth Amendment.

(c) See Item 3.

(d) Not applicable. See Item 3.

(e) Pinon Foundation ceased being deemed to beneficially own more that than five percent of the common shares of the Issuer on November 15, 2017, upon the sale of Issuer’s Series A Preferred Shares to Longfellow.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

There are no changes to the Item 6 information previously filed.

Item 7. Material to be Filed As Exhibits.

Exhibit	Description	Filing
1	Joint Filing Agreement	Filed as Exhibit 1 to Fifteenth Amendment to Schedule 13D filed with the SEC on July 12, 2016.

SIGNATURE

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

Date: December 6, 2017

DALEA PARTNERS, LP
By:	Dalea Management, LLC, its general partner
By:	/s/ N. Malone Mitchell, 3rd
Name:	N. Malone Mitchell, 3rd
Title:	Manager
DALEA MANAGEMENT, LLC
By:	/s/ N. Malone Mitchell, 3rd
Name:	N. Malone Mitchell, 3rd
Title:	Manager
LONGFELLOW ENERGY, LP
By:	Deut 8, LLC, its general partner
By:	/s/ N. Malone Mitchell, 3rd
Name:	N. Malone Mitchell, 3rd
Title:	Manager
DEUT 8, LLC
By:	/s/ N. Malone Mitchell, 3rd
Name:	N. Malone Mitchell, 3rd
Title:	Manager
PINON FOUNDATION
By:	/s/ N. Malone Mitchell, 3rd
Name:	N. Malone Mitchell, 3rd
Title:	Director
/s/ N. Malone Mitchell, 3rd
N. MALONE MITCHELL, 3rd
/s/ Amy Mitchell
AMY MITCHELL