Denne melding til obligasjonseierne er kun utarbeidet på engelsk. For informasjon vennligst kontakt Nordic Trustee ASA

To the bondholders in:

ISIN NO 001 070098.2 - 7.50% Oro Negro Drilling Pte. Ltd. Senior Secured Bond Issue2014/2019

Oslo, 4 March 2016

Summons to Bondholders’ Meeting - proposal for amendments

Nordic Trustee ASA (previously Norsk Tillitsmann ASA) (the “Bond Trustee”) acts as trustee for the bondholders (together, the “Bondholders”) in the abovementioned bond issue (the “Bonds” or the “Bond Issue”), a bond loan of USD 725,000,000 issued by Oro Negro Drilling Pte. Ltd. (the “Issuer”).

Capitalized terms used herein (including any attachment hereto) shall have the meaning assigned to them in the bond agreement dated 24 January 2014 (as amended and restated from time to time) (the “Bond Agreement”), unless otherwise stated herein.

The information in this summons regarding the Issuer and the described transactions is provided by the Issuer, and the Bond Trustee expressly disclaims all liability whatsoever related to such information.

1 BACKGROUND

1.1 Introduction

The Issuer, together with Integradora de Servicios Petroleros Oro Negro, S.A.P.I. de C.V. (the “Parent”) and its subsidiaries (collectively, the “Company”), has been involved in discussions with an ad hoc committee of Bondholders (the “Ad Hoc Bondholder Committee”) and an ad hoc committee (the “2015 Ad Hoc Bondholder Committee”) of holders (the “2015 Bondholders”) of the USD 175,000,000 First Priority Oro Negro Impetus Pte. Ltd. Senior Secured Bond Issue 2014/2015 (the “2015 Bonds”) regarding a comprehensive restructuring of its debt. The Issuer and the Ad Hoc Bondholder Committee have reached an agreement in principle whereby the Bond Agreement would be amended in a manner consistent with the term sheet attached hereto as Exhibit 1 (the “Restructuring Plan”). In connection with implementing the Restructuring Plan, the Issuer will require access to funds which are currently being held as part of the minimum Liquidity requirement pursuant to Clauses 13.4(c) cf. 13.7(a) of the Bond Agreement (the “Liquidity Requirement”). It is anticipated that the forms of definitive agreements with respect to the Restructuring Plan shall be finalized prior to the Bondholders’ Meeting (as defined below) contemplated by this summons and that a summons for a subsequent bondholders’ meeting to approve such agreements shall be posted prior to or on the date of the Bondholders’ Meeting.

This summons letter is issued in order to seek approval from the Bondholders of limited access by the Issuer to funds currently restricted as part of the Liquidity Requirement in the interim period between the Effective Date of the Proposal (each, as defined below) and the Bondholders’ approval of definitive documentation to implement the Restructuring Plan.

2 THE PROPOSAL

In accordance with Clause 16.2 of the Bond Agreement, the Issuer has approached the Bond Trustee to convene a meeting of Bondholders (“Bondholders’ Meeting”) to consider the Issuer’s request to(i) waive, until April 8, 2016, the requirement that the Issuer maintain a minimum Liquidity of USD 5,000,000 (US Dollars five million) per Rig as set forth in Clause 13.7(a) of the Bond Agreement, and(ii) permit the use of funds in the Issuer Earnings Account after giving effect to such waiver for the operation of the business associated with the Rigs (including the payment of the allocable portion of any selling, general and administrative expenses of the Issuer and amounts due and payable by any Parent Group Company in respect of the Rigs); provided that each Parent Group Company shall at all times operate solely in compliance with the weekly cash budget attached as Exhibit 2 hereto (with limited allowances for variances as described in the definition of “Permitted Deficit” below), all as set out in detail below (the “Proposal”):

1. Clause 1.1 o f the Bond Agreement to be amended to add the following definition immediately before the definition o f "Business Day ” to read:

"Budget” means the weekly cash budget attached hereto as Attachment 6.

2. Clause 1.1 o f the Bond Agreement to be amended to add the following defin ition immediately before the definition o f "Escrow Account” to read:

“Emergency Operational Expense ” means each expense not otherwise included in the Budget (a) incurred by any Parent Group Company in connection with (1) (i) expedited repair or replacement o f any equipment due to damage or failure thereof that materially impairs the operation o f any Rig, (ii) any medical emergency involving personnel involved in the operation o f the Rigs, (Hi) any chemical spill or other ongoing environmental hazard situation related to the Rigs, (iv) any other extraordinary emergency related to the Rigs that a Parent Group Company has a legal or contractual obligation to remedy, (v) any imminent hazard that would reasonably be expected to result in any o f the foregoing, or (vi) any expedited equipment modification, addition or substitution required by the customer under any Drilling Contract in order to commence or continue operation o f any Rig and without which the operation o f such Rig would be delayed or halted by such customer, in each case that is beyond the reasonable control o f the Company and that could not be prevented or overcome by the commercially reasonable efforts, precautions, care and due diligence o f the Company, or (2) such other uses as may be approved by by holders o f at least 33% o f the Bonds by written notice to the Trustee; and (b) in connection with which the applicable Parent Group Company shall have delivered an officer’s certificate executed by the chief financial officer o f the Parent to the Bond Trustee, in the form attached hereto as Attachment 7, prior to the date o f any payment in respect o f an Emergency Operational Expense, identifying such payment and the amount thereof (stated in US Dollars) and certifying that such payment is in respect o f an expense incurred under the circumstances described in the foregoing clause (a); provided that in the event that any Emergency Operational Expense exceeds USD 300,000 (US Dollars three hundred thousand) for any single event, or all such Emergency Operational Expenses incurred within any three-week period exceed USD 1,500,000 (US Dollars two million) in the aggregate, any amount in excess thereof shall not be considered an Emergency Operational Expense.

3. Clause 1.1 o f the Bond Agreement to be amended to add the following definition immediately before the definition o f “PPL ” to read:

"Permitted Deficit” means, as o f the end o f any calendar week set forth in the Budget, a cumulative deficit for such calendar week (after giving effect to any cumulative budgetary

surplus as o f the end o f the immediately preceding calendar week and excluding all Emergency Operational Expenses incurred during such calendar week) from the Budget not exceeding 10% o f the Budget for such calendar week

4. Clause 13.7(a) o f the Bond Agreement to be amended and restated in its entirety to read:

“The Issuer shall, on a consolidated basis, at all times from and after April 8, 2016, have a minimum Liquidity o f USD 5,000,000 (US Dollars five million) per Rig (as applicable). Prior to April 8, 2016, any monies which would otherwise be held in the Issuer Earnings Account shall only be used to fund operations o f the Rigs (including, but not limited to, the allocable portion o f sales, general and administrative expenses, or other costs associated therewith and including through the advancement o f monies to other Parent Group Companies necessary for such purpose) and to pay amounts due and payable by the Charterer or other Parent Group Companies in respect o f the Rigs and the costs o f advisors o f the Bondholders and/or the costs o f the restructuring advisors to the Issuer related to the restructuring o f the Issuer’s debt, in each case to the extent not constituting success fees or other one-time fees; provided that such funds shall at all times be applied in accordance with the Budget and that such payments (calculated in the aggregate on a weekly basis) shall not result in a deficit in excess o f a Permitted Deficit from the Budget. ”

The Proposal shall be effective on the date (the “Effective Date”) on which each of the following conditions precedent have been satisfied (or waived), as determined by the Bond Trustee:

(i) confirmation from the Bond Trustee to the Issuer of a due approval by the necessary 2/3 majority of Voting Bonds represented at the Bondholders’ Meeting, as per Clause 16.3.5 of the Bond Agreement;

(ii) an amendment agreement to the Bond Agreement duly documenting the resolutions of the Bondholders’ Meeting and duly executed by the Issuer, all other Obligors and any other person being a party to any document creating a Security Interest in favour of the Bond Trustee;

(iii) the approval by the 2015 Bondholders of a liquidity proposal and the effectiveness of such liquidity proposal, in form and substance satisfactory to the Ad Hoc Bondholder Committee, which condition may be waived by holders of at least 33% of the Bonds by written notice to the Trustee;

(iv) the delivery to the Bond Trustee of any legal opinions as may be reasonably required by the Bond Trustee in relation to the implementation of the Proposal and confirming the due execution by the parties thereto of the amendment agreement referred to in item (ii) above;

(v) all necessary corporate resolutions of all the parties (except the Bond Trustee) to the amendment agreement referred to in item (ii), above, having been duly made and delivered to the Bond Trustee;

(vi) either:A. a restructuring support agreement attaching agreed forms of definitive documentation

implementing a restructuring of the Bonds (including the forms of an amended and restated Bond Agreement, amended security documents and other attachments thereto) (the “Definitive Documentation”), duly executed by (a) the Company, (b) Sommerville Investments BY, ACOF III Oro Cooperatief U.A., Axis Oil Field

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Holding, S. de R.L. de C.V., and Axis Oil Field Services, S. de R.L. de C.V. (collectively, the “Parent Shareholders”), (c) the Issuer, (d) Oro Negro Impetus Pte. Ltd., (e) each member of the Ad Hoc Bondholder Committee, and (I) each member of the 2015 Ad Hoc Bondholder Committee, pursuant to which the Issuer has irrevocably agreed to enter into the definitive documentation in the form attached thereto; provided that (x) the Company shall be permitted to waive the failure of the condition stated in the foregoing clause (e) if (1) Bondholders holding at least 33.33% of the aggregate outstanding principal amount of the Bonds and (2) members of the Ad Hoc Bondholder Committee holding at least 75% of the aggregate outstanding principal amount of the Bonds held by the Ad Hoc Bondholder Committee as a whole, shall have executed such restructuring support agreement and (y) the Company shall be permitted to waive the failure of the condition stated in the foregoing clause (f) if (1) 2015 Bondholders holding at least 33.33% of the aggregate outstanding principal amount of the 2015 Bonds and (2) members of the 2015 Ad Hoc Bondholder Committee holding at least 75% of the aggregate outstanding principal amount of the 2015 Bonds held by the 2015 Ad Hoc Bondholder Committee as a whole, shall have executed such restructuring support agreement; or

B. the issuance (which shall not have been withdrawn) by the Bond Trustee of a summons to a meeting of Bondholders and a summons to a meeting of the 2015 Bondholders (each in form and substance satisfactoiy to the Ad Hoc Bondholder Committee and the 2015 Ad Hoc Bondholder Committee), attaching the Definitive Documentation, and the execution of an irrevocable commitment by the Issuer, the Company and the Parent Shareholders to duly execute and deliver the Definitive Documentation in the form attached to such summons;

provided that if the following condition has not been satisfied (or waived), as determined by the Bond Trustee, within three (3) Business Days after the Effective Date, the Proposal shall no longer be effective, and the Bond Agreement in effect shall be that in effect prior to the Proposal and the terms of the Bond Agreement will continue in force as if such terms had not been amended by the Proposal:

(a) all fees and expenses incurred by the legal and financial advisors to the Ad Hoc Bondholder Committee (other than success fees) having been reimbursed by the Company in full;

provided, further, that if the following condition has not been satisfied (or waived), as determined by the Bond Trustee, the Proposal shall no longer be effective, and the Bond Agreement in effect shall be that in effect prior to the Proposal and the terms of the Bond Agreement will continue in force as if such terms had not been amended by the Proposal:

(a) due execution and delivery of the Definitive Documentation, in the agreed forms referred to in item (vi) above, on or prior to 5 p.m. (Oslo time) on April 8, 2016.

3 Further information

Bondholders may contact the financial advisors (“Advisors”) as follows for further information:

Moelis & Co.

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Zul Jamale-mail: zul.iamal@,moelis.com telephone: +1 (212) 883 3813

The Advisors act solely for the Issuer and no one else in connection herewith. No due diligence investigations have been carried out by the Advisors with respect to the Issuer, and the Advisors expressly disclaim any and all liability whatsoever in connection with the Proposal (including but not limited to the information contained herein).

For further questions to the Bond Trustee, please contact Olav Slagsvold at mail@nordictrustee.com or + 47 22 87 94 00.

4 Evaluation and non-reliance

The Proposal is put forward to the Bondholders without further evaluation or recommendations from the Bond Trustee. Nothing herein shall constitute a recommendation to the Bondholders by the Bond Trustee. The Bondholders must independently evaluate whether the Proposal is acceptable and vote accordingly.

5 SUMMONS FOR BONDHOLDERS’ MEETING

Bondholders are hereby summoned to a Bondholders’ Meeting:

Time: 21 March 2016 at 13:00 hours (Oslo time)

Place: The premises of Nordic Trustee ASA,Haakon VHs gt 1, 0161 Oslo - 6th floor

Agenda:1. Approval of the summons.2. Approval of the agenda.3. Election of two persons to co-sign the minutes together with the chairman.4. Request for adoption of the Proposal:

It is proposed that the Bondholders’ Meeting resolves the following:

“The Bondholder’s Meeting approves the Proposal as described in section 2 o f the summons for the Bondholders ’ Meeting and directs the Bond Trustee to prepare and make available to the Issuer and the Bondholders (by electronic mail i f requested) a conformed copy o f the Bond Agreement incorporating the amendments made to the same by the Proposal (if passed) and all previous amendment agreements, as soon as practicable. ”

“The Bond Trustee is hereby authorised to execute and deliver an amendment agreement adopting the proposed amendments set out in items 1-4 o f the Proposal as defined in the summons to the Bondholder’s Meeting dated21 March 2016. ”

To approve the above resolution, Bondholders representing more than 2/3 of the Bonds represented in person or by proxy at the Bondholders’ Meeting must vote in favour of the resolution. In order to have a quorum, at least 1/2 of the Voting Bonds must be represented at the meeting.

Please find attached a Bondholder’s Form from the Securities Depository (VPS), indicating your bondholding at the printing date. The Bondholder’s Form will serve as proof of ownership of the Bonds and of the voting rights at the Bondholders’ Meeting. (If the bonds are held in custody - i.e. the

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owner is not registered directly in the VPS - the custodian must confirm; (i) the owner of the bonds, (ii) the aggregate nominal amount of the bonds and (iii) the account number in VPS on which the bonds are registered.)

The individual Bondholder may authorise the Bond Trustee to vote on its behalf, in which case the Bondholder’s Form also serves as a proxy. A duly signed Bondholder’s Form, authorising the Bond Trustee to vote, must then be returned to the Bond Trustee in due time before the meeting is scheduled (by scanned e-mail, telefax or post to post@trustee.no, +47 22 87 94 10, or Nordic Trustee ASA, PO Box 1470 Vika, 0116 Oslo, Norway).

In the event that Bonds have been transferred to a new owner after the Bondholder’s Form was made, the new Bondholder must bring to the Bondholders’ Meeting or enclose with the proxy, as the case may be, evidence which the Bond Trustee accepts as sufficient proof of the ownership of the Bonds.

For practical purposes, we request those who intend to attend the Bondholders’ Meeting, either in person or by proxy other than to the Bond Trustee, to notify the Bond Trustee by telephone or by e- mail (at set out at the first page of this letter) within 16:00 hours (4 pm) (Oslo tune) the Business Day before the meeting takes place.

Yours sincerely Nordic Trustee ASA

Enclosed: Schedule A - Bondholder’s FormExhibit 1 - Bond Agreement Amendment Term Sheet Exhibit 2 - Weekly Cash BudgetExhibit 3 - Form of Emergency Operational Expense Certificate

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SCHEDULE A

negroGlobal Term Sheet

M a rch 4 ,2 0 1 6

EXHIBIT 1

M O E L I S &^C O M P A N Y

KIRKLAND 8v ELLIS LLP

8 | P a g e

Summary of Key Terms of the Combined Secured FacilityGlobal Term Sheet KIRKLAND 8. ELLIS LLP

M O E L I S O M P A N Y

T h e b elo w tab le su m m arizes p ro p o sed in d icative term s availab le u n d er th e C om b in ed S ecu red F acility

* 2015 Bonds and 2019 Bonds are merged into new Combined Secured Facility, secured by all five (5) existing rigs and consisting of:

— Combined Secured Facility: $[921.4]1 mm total principal amount of 7.5 % senior secured bonds due 24 January 2019; consisting of $175.0 mm held by the 2015 Bondholders, $701.0 mm held by the 2019 Bondholders and $45.4 mm of accrued interest under the 2015 and 2019 Bonds

Overview~~ Make-whole payment at 103% to be due upon a refinancing, repayment or acceleration

* Shareholders to fund shareholder settlement payments

■ Company to enter into a receivables factoring facility reasonably satisfactory to the Bondholders, with failure to closeprior to [______ ], 2016 being an event of default

■ Payment of $[31.9] mm accrued interest under 2019 Bonds and $[8.0] mm of accrued interest under 2015 Bonds to be made from the first $[39.9] mm of proceeds from receivables factoring

Amortization & Accrued Interest

Combined Secured Facility: Annual amortization under Combined Secured Facility of $35.0 mm ($7.0 mm / rig)

~~ Interest and amortization payments to be made quarterly

Guaranty and Security

Earnings swept into Issuer Earnings Account from Trust Account; all payments to be made from single waterfall

Parent SG&A expenses to be moved into Issuer; operating expenses to be paid by Issuer rather than Charterer

1 All numbers subject to update for accrued interest.

Summary of Key Terms of the Combined Secured FacilityGlobal Term Sheet KIRKLAND & ELLIS LLP

------------------------------------------------------------------------------------------------------------------------------------------------- M O E L I S S ^ C O M P A N Y

* Parent guaranty of up to $175.0 mm to be provided in respect of the Combined Secured Facility; Charterer required to remain a subsidiary of Parent; Charterer shares pledged as security

■ Issuer debt service and minimum liquidity accounts pledged and blocked; dry dock reserve account pledged and blocked

ECF Sweep100% ECF sweep after amortization,2 but sweep payable only after Company's unrestricted cash is in excess of $20.0 mm

* Elimination of minimum bareboat concept in light of changes to use of Issuer Earnings Account putting all cash flow within the credit

■ Issuer to pay all expenses related to the business (i.e., the management and operation of the 5 rigs)

Amendments / Waivers to

Covenants and Events of Default

■ Material deviations (either greater or lower) from annual capex or (greater than) opex budget provided to bondholders (with exceptions for punchlist items or other items subject to good faith dispute) to constitute event of default

■ Approval of necessary amendments and carve outs for establishing Accounts Receivable Factoring Facility of approximately $[110] mm

■ Suspension of Asset Coverage Ratio covenant for so long as 5 rigs are operating with PEMEX

■ Elimination of Equity Ratio

■ Minimum liquidity to be reduced to $4.0 mm / rig ($20.0 mm in total)

■ Temporary resets of other financial covenants

2 Sweep is based on consolidated net income and applies to cash flow after rig operating expenses, Parent SG&A expenses moved to Issuer, rig maintenancecosts, taxes, interest, amortization, applicable restructuring fees, unrestricted cash catch-up and other contingency reserves.

Summary of Key Terms of the Combined Secured FacilityGlobal Term Sheet KIRKLAND ELLIS LLP

M O E L I S o.;_C O M P A N Y

Uses of Cash

Dividends

■ Complete mutual release of bondholders, officers, directors and shareholders to be effective upon approval of transactions by bondholders

* Waiver of specified defaults

* Up to $25mm of unrestricted cash on hand at the Parent level may only be used to fund operating and restructuring expenses, including all restructuring advisors; payment of fees of advisors to resume upon execution by the Company and the 2015 Bondholders and 2019 Bondholders of a restructuring support agreement and in any event be current as of closing

■ Capex/opex budget of the business for 2016 to be approved by Bondholders prior to closing, with updates provided to Bondholders annually

■ No Bondholder consent right with respect to Company budgets or management changes

■ Shareholder matters to be resolved, with payments made by shareholders

* No dividends to Parent to be permitted other than amounts to cover administrative expenses of Parent (e.g., taxes accrued at parent level, etc.), subject to an annual cap of $3.0 mm and an aggregate cap of $10.0 mm and payable following debt service set-asides, payment of opex/capex and dry dock reserve and meeting of $20.0 mm minimum liquidity requirements

No dividends to shareholders while bonds remain outstanding

EXHIBIT 2

Oro Negro3 Week Budget Requirements (Cash Flows Related to the 2019 Bond) Last Update: March 3, 2016

(In $USD, thousands)For the week ending Friday:

Proj. Proj. Proj. 3-WeekRef Concept Notes 3/25/16 4/1/16 4/8/16 Total

Accounts Receivable Detail (with VAT)i Beginning Balance of Accounts Receivable Balance $ 77,750 $ 77,750 $ 77,750 $ 77,7502 (+) Invoicing - - - -3 (-) Cash Collections - - - -4 Ending Balance of Accounts Receivable Balance $ 77,750 s 77,750 s 77,750 s 77,750

5 Amount of Unrestricted Cash (Initial - Consolidated) $ 515 $ 0 $ - $ 515

6 Collections (with VAT) - - - -7 Access to Restricted Cash 9,099 1,292 1,392 11,783

8 Direct OpEx9 Personnel Outflows (3,488) (333) (549) (4,370)

10 R&M (940) (255) (255) (1,450)11 Direct Operating Costs (1,684) (83) (133) (1,900)12 Direct Onshore Support (405) (94) - (499)

13 SG&A Expense (368) (96) (98) (562)14 Professional Fees (2,005) - - (2,005)

15 CAPEX, OFE and Mobilization - (230) - (230)16 Taxes (247) (100) (176) (523)

17 Bareboat Payment From Collections - - - -

18 Rig 3 / Other Parent Expenses Allocation [1] (478) (101) (179) (759)

19 Total Cash Disbursements $ (9,614) $ (1,292) s (1,392) $ (12,298)

20 Estimated Cash Shortfall $ 0 s - $ - s 0Estimated Restricted Cash Balances

21 Rig Owner Earnings Account $ 20 $ 20 $ 2022 Issuer Earnings Account 24,112 22,820 21,42823 Debt Service Reserve Account 29,339 29,339 29,33924 Total Restricted Cash $ 53,471 s 52,179 s 50,788

Issuer Earnings Account Roll Forward25 Beginning Balance $ 33,211 $ 24,112 $ 22,820 $ 33,21126 (+) Inflows - - - -27 (-) Outflows (9,099) (1,292) (1,392) (11,783)28 Ending Balance $ 24,112 $ 22,820 $ 21,428 s 21,428Notes:[1] Rig 3 and Other Parent Expenses are allocated 80/20, 2019 and 2015 bond respectively

EXHIBIT 3

Form of Emergency Operational Expense Certificate

The undersigned, being the chief financial officer of Integradora de Servicios Petroleros Oro Negro, S.A.P.I. de C.V., hereby certifies to Nordic Trustee ASA, in its capacity as the Bond Trustee under the 7.50% Oro Negro Drilling Pte. Ltd. Senior Secured Bond Issue 2014/2019 (the “2019 Bond Issue”), that the following expenses are not included in the Budget and are due and payable as a result of one of the circumstances described in clause (a) of the definition of “Emergency Operational Expense” contained in the bond agreement governing the 2019 Bond Issue having occurred.

Expense Amount ($)

Sincerely,

Miguel Ångel Villegas Vargas Chief Financial Officer (Interim)