Exhibit 10.9.1

Execution Copy

SCA - GMSL (1)

DATED THE 21^st DAY OF MARCH 2012

INTERNATIONAL CABLESHIP PTE LTD

GLOBAL MARINE SYSTEMS LIMITED

SUPPLEMENTAL CHARTER AGREEMENT

CONTENTS

THIS SUPPLEMENTAL CHARTER AGREEMENT is made on 21^st MARCH 2012

BETWEEN:

(hereinafter collectively referred to as the Parties and each a Party).

WHEREAS:

(B) Pursuant to the bareboat charter agreement dated 24 September 1992 entered into between the Owner and the Charterer, as amended or modified from time to time (Charter Agreement), the Owner has agreed to provide the Charterer with a vessel, the CS Cable Retriever (GMSL Vessel), at an annual Hire Fee (as defined therein) payable in four equal quarterly instalments.

(C) The Parties have agreed to (i) certain amendments to the Charter Agreement as set out in this Supplemental Charter Agreement and (ii) certain amendments to the Joint Venture Agreement as set out in a supplemental Joint Venture Agreement (Supplemental Joint Venture Agreement) to be entered into at or about the same time as this Supplemental Charter Agreement.

(D) The Parties have agreed to enter into this Supplemental Charter Agreement to amend the Charter Agreement on the terms and subject to the conditions contained in this Supplemental Charter Agreement.

IT IS AGREED as follows:

1.1 In this Supplemental Charter Agreement, unless the subject or context otherwise requires, the words and phrases used herein shall have the same meaning ascribed to them in the Charter Agreement and the Supplemental Joint Venture Agreement.

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2.1 In consideration of the foregoing and the mutual covenants set forth in this Supplemental Charter Agreement, the Parties agree to amend the Charter Agreement in accordance with the terms of this Supplemental Charter Agreement.

Business Day means a day (excluding Saturdays, Sundays and public holidays) on which banks generally are open in Singapore for the transaction of normal banking business;

Effective Date means the date of this Supplemental Charter Agreement; and

Master Agreement means the master agreement between SingTel, ACPL, GMSL and the Company dated

29(b) Unless otherwise agreed by the parties, the Charterer shall pay the foregoing Hire Fees for each calendar year (1^st January to 31^st December), in four equal quarterly instalments, the quarters beginning on the first days of January, April, July, October, payment being due sixty days after the start of the quarter to which the instalment applies. If the Vessel is chartered for only part of the calendar year, then the Charterer shall pay a proportion of the annual Hire Fees equal to the proportion of the year the Vessel is chartered. The Owners shall be entitled to charge interest on all payments not received by the due date at a rate of 3% above the lending rate of the Development Bank of Singapore Limited from the date the payment became due until payment is received.

34A The Owner shall have the option, without prejudice to any other right or remedy available to it at law or in equity against the Charterer under this Charter Agreement, to terminate this Charter Agreement and withdraw the GMSL Vessel from service at anytime during the period of this Charter Agreement if any of the Triggering Events set out in Clause 13A.1 of the Supplemental Joint Venture Agreement in relation to the Charterer occurs and if capable of remedy is not remedied before the Cure Date (as defined in the Supplemental Joint Venture Agreement) and no conduct of the Owner or their representatives shall constitute any waiver of the Owner’s rights under this clause.

34B On termination of this Charter Agreement, the following shall apply without prejudice to any other right or remedy available to the Owner at law or in equity against the Charterer under this Charter Agreement:

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Clause 36—Notices

provided that in each case where delivery by hand or by fax occurs after 6pm on a Business Day or on a day which is not a Business Day, service shall be deemed to occur at 9am on the next following Business Day. References to time in this clause are to local time in the country of the addressee.

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Clause 37—Law & Jurisdiction

2.8 Schedule 1 of the Charter Agreement is hereby deleted and replaced with a new Schedule 1 as set out in Annex A hereto.

2.9 Subject to the terms and conditions in the Master Agreement, the amendments set out in Clause 2 of this Agreement shall take effect from the Effective Date.

3.1 Save only as amended or superseded by this Supplemental Charter Agreement, all the provisions of the Charter Agreement and all other instruments and agreements executed thereunder signed by any party hereto shall continue in full force and effect.

3.2 This Supplemental Charter Agreement shall be construed as one with the Charter Agreement. Accordingly, the terms “Charterparty” and “Charter” referred to in the Charter Agreement and all other instruments and agreements executed thereunder or pursuant thereto shall for all purposes refer to the Charter Agreement incorporating and as amended by this Supplemental Charter Agreement.

In the event of any inconsistency between any of the provisions of this Supplemental Charter Agreement and the provisions of the Charter Agreement, the provisions of this Supplemental Charter Agreement shall prevail.

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Unless otherwise provided in this Supplemental Charter Agreement, each of the Parties shall bear its own costs and expenses incurred in connection with the negotiation, preparation and execution of this Supplemental Charter Agreement.

The rights of the parties under this Supplemental Charter Agreement are cumulative and do not exclude or restrict any other rights (except as otherwise provided in this Supplemental Charter Agreement).

No failure or delay by a party to exercise any right under this Supplemental Charter Agreement or otherwise will operate as a waiver of that right or any other right nor will any single or partial exercise of any such right preclude any other or further exercise of that right or the exercise of any other right.

If any provision of this Supplemental Charter Agreement is not or ceases to be legal, valid, binding and enforceable under the law of any jurisdiction, neither the legality, validity, binding effect or enforceability of the remaining provisions under that law nor the legality, validity, binding effect or enforceability of that provision under the law of any other jurisdiction shall be affected.

This Supplemental Charter Agreement shall not be altered, changed, supplemented, or amended except by written instruments signed by the parties.

10.1 Each of the parties shall keep confidential any information received or obtained in connection with this Supplemental Charter Agreement (or any agreement entered into pursuant to this Supplemental Charter Agreement) which relates to:

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Each party agrees, at its own expense, on the request of the other party, to do everything reasonably necessary to give effect to this Supplemental Charter Agreement and the transactions contemplated by it (including the execution of documents) and to use all reasonable endeavours to cause relevant third parties to do likewise.

This Supplemental Charter Agreement may be executed in one or more counterparts (which may be delivered by way of facsimile, mail or electronic PDF copies), each of which shall be deemed to be an original, but all of which together shall constitute one and the same instrument.

This Supplemental Charter Agreement is binding on the successors of each party and, where applicable, the personal representatives of a party.

No party may assign any of the rights or obligations of that party under this Supplemental Charter Agreement without the prior written consent of the other party (such consent not to be unreasonably conditioned, withheld or delayed).

A person who is not a party to this Supplemental Joint Venture Agreement shall have no right under the Contracts (Rights of Third Parties) Act (Cap. 53B) to enforce any of its terms.

Clause 37 of the Charter Agreement (as set out above) shall similarly be applicable to this Supplemental Charter Agreement.

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IN WITNESS WHEREOF this Agreement has been signed on behalf of the Parties on the date stated at the beginning of the document.

The Parties

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ANNEX A

Schedule 1

Demise Charterparty

ICPL HIRE FEE (GMSL)

Note 1: In addition to S$19,489,000 payable in FY2011/12.

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