8-K MACH NATURAL RESOURCES LP

. Entry Into a Material Definitive Agreement.

Credit Agreement Amendment

On
September 12, 2025, the Company entered into a First Amendment to Credit Agreement, together with certain of its subsidiaries party
thereto, the lenders and issuing banks party thereto and Truist Bank, as administrative agent and collateral agent (the “First
Amendment”), which amends that certain Credit Agreement, dated as of February 27, 2025, among the Company, the lenders and
issuing banks party thereto from time to time and Truist Bank, as administrative agent and collateral agent (as amended, restated,
supplemented or otherwise modified from time to time prior to the First Amendment, the “Credit Agreement” and, the
Credit Agreement as amended by the First Amendment, the “Amended Credit Agreement”). The First Amendment, among other
things, (a) removes the 0.10% per annum credit spread adjustment otherwise applicable to the determination of Term SOFR (as defined
in the Credit Agreement), (b) excludes up to $750,000,000 in principal amount of Borrowing Base Reduction Debt (as defined in the
Credit Agreement) issued prior to December 31, 2025 from the provisions otherwise requiring a borrowing base reduction as a result
of the issuance of such indebtedness, (c) if the Sabinal Acquisition closes on a date prior to the IKAV Acquisition, upon closing of
the Sabinal Acquisition and subject to conditions precedent set forth in the First Amendment, provides for (i) a $365,000,000
increase in the borrowing base under the Credit Agreement and (ii) the establishment and funding of term loan commitments in an
amount of $115,000,000, (d) if the IKAV Acquisition closes on a date prior to the Sabinal Acquisition, upon closing of the IKAV
Acquisition and subject to conditions precedent set forth in the First Amendment, provides for (i) a $500,000,000 increase in the
borrowing base under the Credit Agreement and (ii) the establishment and funding of term loan commitments in an amount of
$250,000,000, (e) upon closing of both the Sabinal Acquisition and the IKAV Acquisition (whether on the same date or different
dates) and subject to the conditions precedent set forth in the First Amendment, provides for (i) a $700,000,000 aggregate increase
in the borrowing base under the Credit Agreement and (ii) the establishment of aggregate term loan commitments (prior to giving
effect to any prior funding of term loans) in an amount of $450,000,000 and the funding of any unfunded term loan commitments
thereunder and (f) upon closing of either or both of the Sabinal Acquisition and the IKAV Acquisition an increase in the Aggregate
Elected Revolving Commitment Amount (as defined in the Credit Agreement) to $1,000,000,000.

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Pursuant
to the Amended Credit Agreement, the Initial Term Loans (as defined in the Amended Credit Agreement) funded pursuant to the commitments
established by the First Amendment, will mature on February 27, 2029 and bear interest at a rate equal to, at the election of the Company,
Term SOFR (as defined in the Amended Credit Agreement) plus a margin of 4.00% per annum or ABR (as defined in the Amended Credit Agreement)
plus a margin of 3.00% per annum; provided that, in each case, the margin shall increase by 0.25% per annum on each three-month anniversary
of the first funding date of the Initial Term Loans. In addition, under the Amended Credit Agreement, the Initial Term Loans are required
to be prepaid with the proceeds of certain material issuances of indebtedness after the funding of the Initial Term Loans.

On
September 16, 2025, in connection with the closings of both the Sabinal Acquisition and the IKAV Acquisition on the same date, the term
loan commitments were fully funded in an amount equal to $450,000,000.

The
foregoing description of the First Amendment and the Amended Credit Agreement is a summary only, does not purport to be complete, and
is qualified in its entirety by reference to the full text of the First Amendment, which is filed herewith as Exhibit 10.1 to this Current
Report on Form 8-K (this “Current Report”) and incorporated herein by reference.

IKAV Purchase Agreement Amendment

On September 16, 2025, the
Company entered into that certain First Amendment to the IKAV Purchase Agreement (the “IKAV Purchase Agreement Amendment”)
with the IKAV Sellers, pursuant to which the IKAV Purchase Agreement was amended to reduce the Base Price (as defined in the IKAV Purchase
Agreement) payable to the IKAV Sellers by reducing the IKAV Unit Consideration (as defined herein) to 30,611,264 common units.

The foregoing description
of the IKAV Purchase Agreement Amendment is a summary only, does not purport to be complete and is qualified in its entirety by reference
to the full text of the IKAV Purchase Agreement Amendment, which is filed herewith as Exhibit 2.3 to this Current Report and incorporated
herein by reference.

Registration Rights
Agreement

The
disclosure set forth in Item 2.01 below regarding the Registration Rights Agreement (as defined below) is incorporated by reference into
this Item 1.01.

. Completion of Acquisition or Disposition of Assets.

The
disclosure set forth in the “Introductory Note” above is incorporated into this Item 2.01 by reference.

Sabinal Acquisition

The
Sabinal Acquisition closed on September 16, 2025. The purchase price for the Sabinal Assets was $486.6 million, which was comprised of
(i) cash in the amount of $207.3 million and (ii) 19,187,581 common units representing limited partner interests in the Company (“Common
Units”) (the “Sabinal Unit Consideration”), net of preliminary and customary purchase price adjustments and subject
to final post-closing settlement. The Sabinal Unit Consideration was issued pursuant to the exemption from securities registration afforded
by Section 4(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”).

The
foregoing description of the Sabinal Acquisition is a summary only, does not purport to be complete, and is qualified in its entirety
by reference to the Sabinal Purchase Agreement, which is filed herewith as Exhibit 2.1 to this Current Report and incorporated herein
by reference.

IKAV Acquisition

The
IKAV Acquisition closed on September 16, 2025. The purchase price for the IKAV Assets was $770.7 million, which was comprised of (i) cash
in the amount of $325.0 million and (ii) 30,611,264 Common Units (the “IKAV Unit Consideration”), net of preliminary and customary
purchase price adjustments and subject to final post-closing settlement. The IKAV Unit Consideration was issued pursuant to the exemption
from securities registration afforded by Section 4(a)(2) of the Securities Act.

The
foregoing description of the IKAV Acquisition is a summary only, does not purport to be complete, and is qualified in its entirety by
reference to the IKAV Purchase Agreement, which is filed herewith as Exhibit 2.2 to this Current Report and incorporated herein by reference.

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Registration Rights
Agreement

In
connection with the closing of the Sabinal Acquisition and the IKAV Acquisition, the Company and the Sellers entered into a registration
rights agreement (the “Registration Rights Agreement”). Pursuant to the terms of the Registration Rights Agreement, the Company
will register under the Securities Act the resale of the Sabinal Unit Consideration and the IKAV Unit Consideration. The Registration
Rights Agreement provides for certain additional underwritten demand rights and “piggy-back” registration rights, subject
to certain customary limitations. Additionally, the Sellers have agreed to a 180-day lock-up period with respect to Common Units received.
The Company has also agreed to pay certain expenses of the Sellers incurred in connection with the exercise of their rights under the
Registration Rights Agreement and indemnify the Sellers for certain securities law matters in connection with any registration statement
filed pursuant thereto.

The
foregoing description of the Registration Rights Agreement is a summary only, does not purport to be complete, and is qualified in its
entirety by reference to the full text of the Registration Rights Agreement, which is filed herewith as Exhibit 4.1 to this Current Report
and incorporated herein by reference.

Creation
of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

The
disclosure set forth in Item 1.01 above is incorporated by reference into this Item 2.03.

. Unregistered Sales of Equity Securities.

The
information set forth in the Introductory Note is incorporated by reference in response to this Item 3.02. The issuance of each of the
Sabinal Unit Consideration and the IKAV Unit Consideration was completed in reliance upon the exemption from the registration requirements
of the Securities Act provided by Section 4(a)(2) thereof as a transaction by an issuer not involving any public offering.

. Regulation
FD Disclosure.

A
press release and investor presentation relating to the Sabinal Acquisition and the IKAV Acquisition are attached hereto as Exhibit 99.1
and 99.2, respectively, and are incorporated by reference herein.

The
information furnished pursuant to Item 7.01 in this Current Report, including Exhibits 99.1 and 99.2, is being furnished and shall not be deemed
“filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), nor
shall it be deemed incorporated by reference in any filing under the Securities Act, or the Exchange Act, except as shall be expressly
set forth by specific reference in such filing. You should not assume that the information contained in this Current Report or the accompanying
Exhibits is accurate as of any date other than the date of each such document. Our business, financial condition, results of operations,
prospects and assumptions that were utilized may have changed since those dates.

Financial Statements and Exhibits.

(a) Financial statements of businesses or funds acquired.

The Company intends to file
the financial statements required to be filed pursuant to Item 9.01(a) of Form 8-K by amendment to this Current Report not later than
71 calendar days after the date this Current Report is required to be filed.

(b) Pro forma financial information.

The Company intends to file
the pro forma financial information required to be filed pursuant to Item 9.01(b) of Form 8-K by amendment to this Current Report not
later than 71 calendar days after the date this Current Report is required to be filed.

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(d) Exhibits.

Exhibit No.
 
Description

2.1*
 
Purchase and Sale Agreement, dated as of July 9, 2025, by and among Sabinal Energy Operating, LLC, Sabinal Resources, LLC and Sabinal CBP, LLC, as sellers, and the Company, as buyer (incorporated by reference to Exhibit 2.1 to the Company’s Current Report on Form 8-K filed with the Securities and Exchange Commission on July 10, 2025).

2.2*
 
Membership Interest Purchase Agreement, dated as of July 9, 2025, by and among VEPU Inc. and Simlog Inc., as sellers, and the Company, as buyer (incorporated by reference to Exhibit 2.2 to the Company’s Current Report on Form 8-K filed with the Securities and Exchange Commission on July 10, 2025).

2.3
 
First Amendment to Membership Interest Purchase Agreement, dated as of September 16, 2025, by and among Simlog Inc. and VEPU Inc., as sellers, and the Company, as buyer.

4.1
 
Registration Rights Agreement, dated as of September 16, 2025, by and among Mach Natural Resources LP and each of the sellers party thereto.

10.1*
 
First Amendment to Credit Agreement, dated as of September 12, 2025, by and among the Company, the subsidiaries of the Company party thereto, the lenders and issuing banks party thereto and Truist Bank, as the administrative agent and collateral agent.

99.1
 
Press Release issued September 16, 2025.

99.2
 
Investor Presentation, dated September 16, 2025

104
 
Cover Page Interactive Data File (formatted as Inline XBRL).

*Certain of the schedules and exhibits to the agreement have
been omitted pursuant to Item 601(a)(5) of Regulation S-K. A copy of any omitted schedule or exhibit will be furnished to the
Securities and Exchange Commission upon request.

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