Exhibit 10.3

THIRD AMENDMENT TO EXIM GUARANTEED LOAN AGREEMENT

THIS THIRD AMENDMENT TO EXIM GUARANTEED LOAN AGREEMENT (this "Amendment"), dated as of September 30, 2002, is between HORIZON OFFSHORE
CONTRACTORS, INC., a Delaware corporation ("Contractors"), HORIZON SUBSEA SERVICES, INC., a Delaware corporation ("Subsea"), HORIZON VESSELS, INC., a Delaware corporation
("Vessels"), and HORIZEN, L.L.C., a Delaware limited liability company ("LLC", and together with Contractors, Subsea and Vessels the "Borrowers"), jointly and severally, each of the financial
institutions which is or may from time to time become a party to such Loan Agreement, as amended (collectively, "Lenders", and each a "Lender"), and SOUTHWEST BANK OF TEXAS, N.A., a national
banking association, as agent (the "Agent").

RECITALS:

A.    Borrowers
and Lenders entered into that certain EXIM Guaranteed Loan Agreement dated as of August 15, 2001, as amended by First Amendment to EXIM Guaranteed Loan
Agreement dated as of April 17, 2002 and Second Amendment to EXIM Guaranteed Loan Agreement dated as of August 28, 2002 (the "Agreement").

B.    Pursuant
to the Agreement, each Borrower, Horizon Offshore, Inc., a Delaware corporation, and Horizon Offshore Contractors, Ltd., a company organized and
existing under the laws of the Cayman Islands, each executed a Guaranty dated as of August 15, 2001, and ECH Offshore, S. de R.L. de C.V., a company organized and existing under the laws of
Mexico, executed a Guaranty dated as of August 15, 2001 (under Mexican law) and a Guaranty dated as of May 30, 2002 (under Texas law), pursuant to which such Persons (as defined in the
Agreement) guaranteed to Agent the payment and performance of the Obligations (as defined in the Agreement).

C.    Pursuant
to the Agreement all the other subsidiaries of Parent executed guaranty agreements pursuant to which such subsidiaries guaranteed the obligations of Borrowers
under the Loan Agreement.

D.    Borrowers,
Lenders and Agent now desire to amend the Agreement as herein set forth.

NOW,
THEREFORE, in consideration of the premises herein contained and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties
hereto agree as follows:

ARTICLE I.    Definitions

Section I.1.Definitions.Capitalized terms used in this Amendment, to the extent not otherwise defined
herein, shall have the meanings given to such terms in the Agreement, as amended hereby.

ARTICLE II.    Amendments

Section II.1.Amendment to Certain Definitions.The definition of each of the following terms contained
in Section 1.1 of the Agreement is amended to read in its respective entirety as follows:



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Section II.2.Amendment to Section 9.6.Section 9.6 of the Agreement shall be amended to
read in its entirety as follows.



Section II.3.Amendment to Schedules and Exhibits.Exhibit "V" to the Agreement (No Default Certificate)
is amended to conform in its entirety to Annex "A" to this Amendment.

ARTICLE III.    Conditions Precedent

Section III.1.Conditions.The effectiveness of this Amendment is subject to the receipt by Agent of the
following, each in form and substance satisfactory to Agent and Lenders:



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ARTICLE IV.    Ratifications, Representations, and Warranties

Section IV.1.Ratifications.The terms and provisions set forth in this Amendment shall modify and
supersede all inconsistent terms and provisions set forth in the Agreement and except as expressly modified and superseded by this Amendment, the terms and provisions of the Agreement are ratified and
confirmed and shall continue in full force and effect. Borrowers and Lenders agree that the Agreement as amended hereby shall continue to be the legal, valid and binding obligation of such Persons
enforceable against such Persons in accordance with its terms.

Section IV.2.Representations, Warranties and Agreements.Each Borrower hereby represents and warrants to
Lenders that (a) the execution, delivery, and performance of this Amendment and any and all other Loan Documents executed or delivered in connection herewith have been authorized by all
requisite action on the part of such Borrower and will not violate the Organizational Documents of such Borrower, (b) the representations and warranties contained in the Agreement as amended
hereby, and all other Loan Documents are true and correct on and as of the date hereof as though made on and as of the date hereof, (c) upon the effectiveness of this Amendment no Event of
Default or Unmatured Event of Default will exist, (d) upon the effectiveness of this Amendment Borrowers will be in full compliance with all covenants and agreements contained in the Agreement
as amended hereby, (e) Borrowers are indebted to Lenders pursuant to the terms of the Notes, as the same may have been renewed, modified, extended and rearranged, (f) the liens, security
interests, encumbrances and assignments created and evidenced by the Loan Documents are, respectively, valid and subsisting liens, security interests, encumbrances and assignments and secure the Notes
as the same may have been renewed, modified or rearranged, and (g) no Borrower has any claims, credits, offsets, defenses or counterclaims arising from the Loan Documents or any Lender's
performance under the Loan Documents.

ARTICLE V.    Miscellaneous

Section V.1.Survival of Representations and Warranties.All representations and warranties made in this
Amendment or any other Loan Documents including any Loan Document furnished in connection with this Amendment shall fully survive the execution and delivery of this Amendment and the other Loan
Documents, and no investigation by any Lender or any closing shall affect the representations and warranties or the right of any Lender to rely on them.

Section V.2.Reference to Agreement.Each of the Loan Documents, including the Agreement and any and all
other agreements, documents, or instruments now or hereafter executed and delivered pursuant to the terms hereof or pursuant to the terms of the Agreement, as amended hereby, are hereby amended so
that any reference in such Loan Documents to the Agreement shall mean a reference to the Agreement, as amended hereby.

Section V.3.Expenses.As provided in the Agreement, Borrowers agree to pay on demand all costs and
expenses incurred by Agent in connection with the preparation, negotiation and execution of

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this Amendment and the other documents and instruments executed pursuant hereto and any and all amendments, modifications and supplements thereto, including, without limitation, the costs and fees of
Agent's legal counsel, and all costs and expenses incurred by Agent in connection with the enforcement or preservation of any rights under the Agreement, as amended hereby, or any other Loan Document,
including, without limitation, the costs and fees of Agent's legal counsel.

Section V.4.Severability.Any provision of this Amendment held by a court of competent jurisdiction to
be invalid or unenforceable shall not impair or invalidate the remainder of this Amendment and the effect thereof shall be confined to the provision so held to be invalid or unenforceable.

Section V.5.APPLICABLE LAW.THIS
AMENDMENT AND ALL OTHER LOAN DOCUMENTS EXECUTED PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE AND TO BE PERFORMABLE IN HOUSTON, HARRIS COUNTY, TEXAS AND SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS.

Section V.6.Successors and Assigns.This Amendment is binding upon and shall inure to the benefit of
Agent, Issuing Bank, each Lender and each Borrower and their respective successors and assigns, except that no Borrower may assign or transfer any of its rights or obligations hereunder without the
prior written consent of Agent.

Section V.7.Counterparts.This Amendment may be executed in one or more counterparts, each of which when
so executed shall be deemed to be an original, but all of which when taken together shall constitute one and the same instrument.

Section V.8.Effect of Waiver.No consent or waiver, express or implied, by Agent, Issuing Bank or any
Lender to or for any breach of or deviation from any covenant, condition or duty by any Borrower shall be deemed a consent or waiver to or of any other breach of the same or any other covenant,
condition or duty.

Section V.9.Headings.The headings, captions, and arrangements used in this Amendment are for
convenience only and shall not affect the interpretation of this Amendment.

Section V.10.ENTIRE
AGREEMENT.THIS AMENDMENT AND ALL OTHER INSTRUMENTS, DOCUMENTS, AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH THIS AMENDMENT
EMBODY THE FINAL, ENTIRE AGREEMENT AMONG THE PARTIES HERETO
WITH RESPECT TO THE SUBJECT MATTER HEREOF AND THEREOF AND SUPERSEDE ANY AND ALL PRIOR COMMITMENTS, AGREEMENTS, REPRESENTATIONS AND UNDERSTANDINGS, WHETHER WRITTEN OR ORAL, RELATING TO THIS AMENDMENT
AND THE OTHER INSTRUMENTS, DOCUMENTS AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH THIS AMENDMENT, AND MAY NOT BE CONTRADICTED OR VARIED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT
ORAL AGREEMENTS OR DISCUSSIONS OF THE PARTIES HERETO. THERE ARE NO ORAL AGREEMENTS AMONG THE PARTIES HERETO.

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Executed
as of the date first written above.

| |  | BORROWERS:                                
| |  | ------------------------------------------
| |  | HORIZON OFFSHORE CONTRACTORS, INC.        
| |  | By:David W. Sharp
Executive Vice President
| |  | HORIZEN, L.L.C.                           
| |  | By:R. Clay Etheridge
President            
| |  | HORIZON SUBSEA SERVICES, INC.             
| |  | By:David W. Sharp
Executive Vice President
| |  | HORIZON VESSELS, INC.                     
| |  | By:David W. Sharp
Executive Vice President
| |  | AGENT:                                    
| |  | SOUTHWEST BANK OF TEXAS, N.A., as Agent   
| |  | By:Valerie Gibbs
Senior Vice President    
| |  | LENDERS:                                  
| |  | SOUTHWEST BANK OF TEXAS, N.A.             
| |  | By:Valerie Gibbs
Senior Vice President    

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| |  | DRESDNER BANK LATEINAMERIKA AG          
| |  | ----------------------------------------
| |  | By:Alan Hills
Vice President            
| |  | By:Sergio Goloubeff
First Vice President
| |  | BANK OF SCOTLAND                        
| |  | By:Joseph Fratus
Vice President         
| |  | HIBERNIA NATIONAL BANK                  
| |  | By:Gary Culbertson
Vice President       

Each
of the undersigned Guarantors (a) hereby consents and agrees to this Amendment, (b) agrees that all references to the Loan Agreement contained in the Guaranty
Agreement executed by such Person shall constitute references to such Loan Agreement as amended by this Amendment and as the same
may be further amended, and (c) agrees that the Guaranty Agreement executed by such Person shall remain in full force and effect and shall continue to be the legal, valid and binding
obligations of such Guarantor, enforceable against such Guarantor in accordance with its terms and shall evidence such Guarantor's guaranty of the Notes as renewed, modified and extended from time to
time.

| |  | HORIZON OFFSHORE, INC.                    
| |  | ------------------------------------------
| |  | By:David W. Sharp
Executive Vice President
| |  | HORIZON OFFSHORE CONTRACTORS, LTD.        
| |  | By:David W. Sharp
Director                
| |  | ECH OFFSHORE, S. DE R.L. DE C.V.          
| |  | By:R. Clay Etheridge
Sole Manager         

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| |  | Other Guarantors                                                                                                                                                                                         
| |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |  | PROGRESSIVE PIPELINE CONTRACTORS, INC.
AFFILIATED MARINE CONTRACTORS, INC.
TEXAS OFFSHORE CONTRACTORS CORP.
FLEET PIPELINE SERVICES, INC.
GULF OFFSHORE CONSTRUCTION, INC.
BAYOU MARINE CONTRACTORS, INC.
| |  | By:David W. Sharp
Executive Vice President                                                                                                                                                               
| |  | HORIZON GROUP L.D.C.                                                                                                                                                                                     
| |  | By:David W. Sharp
Director                                                                                                                                                                               
| |  | HORIZON OFFSHORE NIGERIA LTD.                                                                                                                                                                            
| |  | By:David W. Sharp
Director                                                                                                                                                                               
| |  | TIBURON INGENIERIA Y CONSTRUCCION, S.
DE R.L. DE C.V.                                                                                                                                                    
| |  | By:David W. Sharp
Secretary                                                                                                                                                                              
| |  | HORIZON VESSELS INTERNATIONAL LTD.                                                                                                                                                                       
| |  | By:David W. Sharp
Vice President                                                                                                                                                                         
| |  | PT HORIZON INDONESIA                                                                                                                                                                                     
| |  | By:David W. Sharp
Commissioner                                                                                                                                                                           
| |  | HORIZON OFFSHORE INTERNATIONAL LTD.                                                                                                                                                                      
| |  | By:David W. Sharp
Executive Vice President                                                                                                                                                               

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| |  | HORIZON MARINE CONSTRUCTION LTD.              
| |  | ----------------------------------------------
| |  | By:David W. Sharp
Executive Vice President    
| |  | HORIZON OFFSHORE PTE. LTD.                    
| |  | By:David W. Sharp
Director                    
| |  | HORIZON OFFSHORE CONTRACTORS
(MAURITIUS) LTD. 
| |  | By:David W. Sharp
Director                    
| |  | HORIZON MARINE CONSTRUCTION
(MAURITIUS) LTD.  
| |  | By:David W. Sharp
Director                    
| |  | HORIZON C-BAY COSTA AFUERA, S.
DE R.L. DE C.V.
| |  | By:David W. Sharp
Member                      
| |  | HOC OFFSHORE, S. DE R.L. DE C.V.              
| |  | By:R. Clay Etheridge
President                
| |  | PT ARMANDI PRANAUPAYA                         
| |  | By:David W. Sharp
Director                    

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LIST OF ANNEXES

Annex

DocumentA

No Default Certificate


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ANNEX "A"    No Default Certificate

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