Exhibit
4.3


 


Execution Version




 


ION
GEOPHYSICAL CORPORATION,


 


THE GUARANTORS NAMED


 


HEREIN,
AND


 


WILMINGTON
SAVINGS FUND SOCIETY, FSB,


 


as
Trustee,


 


AND


 


WILMINGTON
SAVINGS FUND SOCIETY, FSB,


 


as
Collateral Agent


 


FIRST
SUPPLEMENTAL INDENTURE


 


Dated
as of April 20, 2021 to


 


Indenture


 


Dated
as of April 28, 2016


 


9.125%
Senior Secured Second Priority Notes due 2021


 


THIS
FIRST SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of April 20, 2021, is by and among ION Geophysical
Corporation, a Delaware corporation (the “Issuer”), the Guarantors listed on the signature pages hereof, Wilmington
Savings Fund Society, FSB, as Trustee (the “Trustee”) and Wilmington Savings Fund Society, FSB, as Collateral Agent
(the “Collateral Agent”).


 


WHEREAS,
the Issuer, the Guarantors, the Collateral Agent and the Trustee are parties to the Indenture, dated as of April 28, 2016, providing
for the issuance of the Issuer’s 9.125% Senior Secured Second Priority Notes due 2021 (the “Notes”) (being herein
called the “Indenture”);


 


WHEREAS,
the Notes are secured pursuant to the Indenture and that certain Intercreditor Agreement dated as of April 28, 2016 (the “Existing
Intercreditor Agreement”);


 


WHEREAS,
on April 28, 2016, the Issuer issued $120,569,000 in aggregate principal amount of Notes;


 


WHEREAS,
prior to giving effect to the Exchange Offer (as defined below) $120,569,000 in aggregate principal amount of Notes is currently
outstanding;


 


WHEREAS,
after giving effect to the Exchange Offer $7,097,000 in aggregate principal amount of Notes will be outstanding;


 


WHEREAS,
Section 9.02 of the Indenture provides that, with the consent of Holders of at least a majority in aggregate principal amount
of the then outstanding Notes (including, without limitation, Additional Notes, if any), the Issuer, the Guarantors, the Collateral
Agent and the Trustee may enter into an indenture supplemental to the Indenture for the purpose of amending or supplementing the
Indenture or the Notes (subject to certain exceptions);


 


WHEREAS,
Section 9.02 of the Indenture provides that, with the consent of Holders of at least 66-2/3% in aggregate principal amount of
the then outstanding Notes (including, without limitation, Additional Notes, if any), the Issuer, the Guarantors, the Collateral
Agent and the Trustee may enter into a supplemental indenture that has the effect of releasing all or substantially all of the
Collateral from Liens securing the Notes;


 


WHEREAS,
the execution and delivery of this Supplemental Indenture have been authorized by the Board of Directors of the Issuer;





     


     


    



WHEREAS,
the Issuer desires and has requested the Trustee and the Collateral Agent to join with it and the Guarantors in entering into
this Supplemental Indenture for the purpose of amending the Indenture and the Notes in certain respects and terminating the security
interest under the Indenture and the Existing Intercreditor Agreement as permitted by Section 9.02 of the Indenture;


 


WHEREAS,
in conjunction with the Issuer’s offer to exchange the Notes for notes to be issued under that certain indenture (the “New
Notes Indenture”) dated April 20, 2021, among the Issuer, the Guarantors and UMB Bank, National Association (the “New
Notes Trustee”), as trustee and as collateral agent, the Issuer has solicited consents to the amendments effected by this
Supplemental Indenture, upon the terms and subject to the conditions set forth in the Offer to Exchange dated March 10, 2021,
and the related Consent and Letter of Transmittal (which together, including any amendments, modifications or supplements thereto,
constitute the “Exchange Offer”); and


 


WHEREAS,
(1) Issuer has received the consent of the Holders of at least 66-2/3% in aggregate principal amount of the outstanding Notes
(excluding any Notes owned by Issuer or any of its Affiliates), all as certified by an Officers’ Certificate delivered to
the Trustee simultaneously with the execution and delivery of this Supplemental Indenture, (2) the Issuer has delivered to the
Trustee simultaneously with the execution and delivery of this Supplemental Indenture an Officer’s Certificate and an Opinion
of Counsel relating to this Supplemental Indenture as contemplated by Section 9.06 of the Indenture and (3) the Issuer and the
Guarantors have satisfied all other conditions required under the Indenture, including without limitation Article 9 thereof, to
enable the Issuer, the Guarantors, the Collateral Agent and the Trustee to enter into this Supplemental Indenture.


 


NOW,
THEREFORE, in consideration of the above premises, each party hereby agrees, for the benefit of the others and for the equal and
ratable benefit of the Holders of the Notes, as follows:


 


ARTICLE
1


 


AMENDMENTS
TO INDENTURE AND NOTES


 


Section
1.1   Amendments to Articles 3, 4, 5 and 6 of the Indenture. The Indenture is hereby amended by deleting the following
Sections or clauses of the Indenture and all references and definitions related thereto in their entirety:


 


Section
3.09 (Offer to Purchase by Application of Excess Proceeds);


 


Clauses (a) - (c) of Section 4.03 (Reports);


 


Section
4.04 (Compliance Certificate);


 


Section 4.05 (Taxes);


 


Section
4.06 (Stay, Extension and Usury Laws);


 


Section 4.07 (Restricted Payments);


 


Section
4.08 (Dividend and Other Payment Restrictions Affecting Restricted Subsidiaries);


 


Section 4.09 (Incurrence of Indebtedness and
Issuance of Preferred Stock);


 


Section
4.10 (Asset Sales);


 


Section
4.11 (Transactions with Affiliates); Section 4.12 (Liens);


 


Section
4.14 (Offer to Repurchase Upon Change of Control);


 


Section 4.15 (Additional Note Guarantees);





     


     


    



Section
4.18 (Further Assurances; Insurance);


 


Section 4.19 (Impairment of Security Interest);


 


Section 4.20 (After-Acquired Property);


 


Section
4.21 (Limitation on Layered Indebtedness);


 


Clause
(iv) of Section 5.01 (Merger, Consolidation or Sale of Assets); and


 


Clauses (v), (vi), ((vii)(A)) and ((vii)(B)) of Section 6.01
(Events of Default).


 


Section
1.2      [Intentionally Omitted.]


 


Section
1.3 Amendment to Section 1.01. Section 1.01 of the Indenture is hereby amended by inserting in proper alphabetical
order the following new definition:


 


“New
Notes Indenture” means that certain Indenture, dated as of April 20, 2021, among the Issuer, the Guarantors, the trustee
thereunder and the collateral agent thereunder, as amended, supplemented or otherwise modified from time to time.


 


Section
1.4 Amendment to Section 4.16. Section 4.16 of the Indenture is hereby amended in its entirety to provide as follows:


 


As
of April 20, 2021, all Subsidiaries of the Company are Restricted Subsidiaries. If, after April 20, 2021, a Subsidiary is designated
a “Restricted Subsidiary” or an “Unrestricted Subsidiary” under the New Notes Indenture, the Board of
Directors of the Company shall similarly designate such Subsidiary as a Restricted Subsidiary or an Unrestricted Subsidiary hereunder.


 


Any
designation of a Subsidiary of the Company as an Unrestricted Subsidiary will be evidenced to the Trustee by filing with the Trustee
a certified copy of a resolution of the Board of Directors giving effect to such designation and an Officers’ Certificate
certifying that such designation complied with the preceding conditions. In the case of any designation by the Company of a Person
as an Unrestricted Subsidiary on the first day that such Person is a Subsidiary of the Company in accordance with the provisions
of this Indenture, such designation shall be deemed to have occurred for all purposes of this Indenture simultaneously with, and
automatically upon, such Person becoming a Subsidiary. If, at any time, any Unrestricted Subsidiary would fail to meet the preceding
requirements as an Unrestricted Subsidiary, it will thereafter cease to be an Unrestricted Subsidiary for purposes of this Indenture.


 


Section
1.5      [Intentionally Omitted].


 


Section
1.6      [Intentionally Omitted].


 


Section
1.7      Amendment to Section 10.01. Section 10.01 of the Indenture is hereby amended by deleting therefrom the phrase “The
Company will take, and will cause its Subsidiaries to take any and all actions necessary or proper or as may be reasonably requested
by the Collateral Agent to cause the Security Documents to create and maintain, as security for the Obligations of the Company
hereunder, a valid and enforceable perfected second priority Lien in and on all the Collateral, in favor of the Collateral Agent
for the benefit of the Holders of Notes, superior to and prior to the rights of all third Persons and subject to no other Liens
other than Permitted Prior Liens.”


 


Section
1.8      Amendments to Notes. The Notes are hereby amended to provide as set forth in Exhibit A attached hereto.


 


Section
1.9      Exhibit G. Exhibit G to the Indenture is hereby deleted.





     


     


    



Section
1.10 Amendment to the Title of the Notes. All references in the Indenture to the title of the Notes as “9.125%
Senior Secured Second Priority Notes due 2021” are hereby amended to read “9.125 % Senior Notes due 2021.”


 


ARTICLE
2


 


SECURITY
INTEREST


 


(1)
Release of Existing Security Interests. Each Security Document in effect immediately prior to this Supplemental Indenture
taking effect, including without limitation the Existing Intercreditor Agreement, is hereby terminated and all Liens granted pursuant
thereto are hereby automatically deemed to be for all purposes fully and irrevocably satisfied, released and terminated without
any further action by any party. The Issuer is hereby authorized to file, or cause to be filed, UCC3 termination statements terminating
the UCC1 financing statements for the Liens granted at any time prior to this Supplemental Indenture taking effect pursuant to
any Security Document, including without limitation the Existing Intercreditor Agreement.


 


ARTICLE
3


 


MISCELLANEOUS
PROVISIONS


 


Section
3.1 Defined Terms. For all purposes of this Supplemental Indenture, except as otherwise defined or unless the context
otherwise requires, terms used in capitalized form in this Supplemental Indenture and defined in the Indenture have the meanings
specified in the Indenture.


 


Section
3.2 Indenture. Except as amended hereby, the Indenture and the Notes are in all respects ratified and confirmed and
all the terms shall remain in full force and effect. This Supplemental Indenture shall form a part of the Indenture for all purposes,
and every Holder of Notes heretofore or hereafter authenticated and delivered under the Indenture shall be bound hereby and all
terms and conditions of both shall be read together as though they constitute a single instrument, except that in the case of
conflict the provisions of this Supplemental Indenture shall control.


 


Section
3.3 Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS
OF THE STATE OF NEW YORK.


 


Section
3.4 Successors. All agreements of the Issuer and the Guarantors in this Supplemental Indenture and the Notes shall
bind their respective successors. All agreements of the Trustee in this Supplemental Indenture shall bind its successors.


 


Section
3.5 Duplicate Originals. All parties may sign any number of copies of this Supplemental Indenture. Each signed
copy shall be an original, but all of them together shall represent the same agreement. It is the express intent of the parties
to be bound by the exchange of signatures on this Supplemental Indenture via telecopy or other form of electronic transmission.


 


Section
3.6 Severability. In case any one or more of the provisions in this Supplemental Indenture or in the Notes shall be
held invalid, illegal or unenforceable, in any respect for any reason, the validity, legality and enforceability of any such provision
in every other respect and of the remaining provisions shall not in any way be affected or impaired thereby, it being intended
that all of the provisions hereof shall be enforceable to the fullest extent permitted by law.


 


Section
3.7 [Intentionally Omitted].


 


Section
3.8 Trustee and Collateral Agent Disclaimer. Each of the Trustee and the Collateral Agent accepts the amendments
of the Indenture effected by this Supplemental Indenture and agrees to execute the trust created by the Indenture as hereby amended,
but on the terms and conditions set forth in the Indenture, including the terms and provisions defining and limiting the liabilities
and responsibilities of the Trustee and the Collateral Agent, which terms and provisions shall in like manner define and limit
its liabilities and responsibilities in the performance of the trust created by the Indenture as hereby amended, and without limiting
the generality of the foregoing, neither the Trustee nor the Collateral Agent shall be responsible in any manner whatsoever for
or with respect to any of the recitals or statements contained herein, all of which recitals or statements are made solely by
the Issuer and the Guarantors, and neither the Trustee nor the Collateral Agent makes any representation with respect to any such
matters. Additionally, neither the Trustee nor the Collateral Agent makes any representations as to the validity or sufficiency
of this Supplemental Indenture.





     


     


    



Section
3.9 Title of the Notes; Endorsement and Change of Form of Notes. Upon the effectiveness of this Agreement, the title
of the Notes shall be “9.125 % Senior Notes due 2021.” Any Notes authenticated and delivered after the close of business
on the date that this Supplemental Indenture becomes effective in substitution for Notes then outstanding, and all Notes presented
or delivered to the Trustee on and after that date for such purpose, shall be (i) affixed to, stamped, imprinted or otherwise
legended by the Issuer with, a notation that provides as follows:


 


“Effective
as of April 20, 2021, substantially all of the restrictive covenants and certain events of default of Issuer have been eliminated
and the second priority security interest in the collateral securing the Notes have been released, as further provided in that
certain First Supplemental Indenture, dated as of April 20, 2021. Reference is hereby made to said First Supplemental Indenture,
copies of which are on file with the Trustee.”


 


and
(ii) in the form of Note attached hereto as Exhibit A.


 


Section 3.10 Effect of
Headings. The Section headings herein are for convenience only and shall not affect the construction thereof.


 


[THE
REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK]





     


     


    



IN
WITNESS WHEREOF, the parties hereto have caused this First Supplemental Indenture to be duly executed as of the day and year written
above.


 





	 	ION
    GEOPHYSICAL CORPORATION
	 	 
	 	By:	/s/ Michael Morrison
	 	Name:
    Michael Morrison
	 	Title:
    Executive Vice President and Chief Financial Officer
	 	 
	 	GX
    TECHNOLOGY CORPORATION
	 	 
	 	By:	/s/ Michael Morrison
	 	Name:
    Michael Morrison
	 	Title:
    Executive Vice President and Chief Financial Officer
	 	 
	 	ION
    EXPLORATION PRODUCTS (U.S.A.), INC.
	 	 
	 	By:	/s/ Michael Morrison
	 	Name:
    Michael Morrison
	 	Title:
    Vice President
	 	 
	 	I/O
    MARINE SYSTEMS, INC.
	 	 
	 	By:	/s/ Michael Morrison
	 	Name:
    Michael Morrison
	 	Title:
    Vice President
	 	 
	 	GX
    GEOSCIENCE CORPORATION, S. DE R.L. DE C.V.
	 	 
	 	By:	/s/ Michael Morrison
	 	Name:
    Michael Morrison
	 	Title:
    Vice President and Attorney-in-Fact







     


     


    



	 	WILMINGTON
    SAVINGS FUND SOCIETY, FSB, as Trustee
    and Collateral Agent
	 	 
	 	By:	/s/ Geoffrey J. Lewis
	 	Name:
    Geoffrey J. Lewis
	 	Title:
    Vice President







     


     


    



EXHIBIT
A


 





	 	CUSIP/CINS	 


 


9.125%
Senior Notes due 2021


 


No.
$                


 


ION
GEOPHYSICAL CORPORATION


 


promises
to pay to _________ or registered assigns,


 


the
principal sum of DOLLARS on December 15, 2021.


 


Interest
Payment Dates: June 15 and December 15, except that the interest otherwise payable on June 15, 2021 will be payable on December
15, 2021.


 


Record
Dates: June 1 and December 1


 


Dated:
____________________


 





	 	ION
    GEOPHYSICAL CORPORATION
	 	 	 
	 	By:	 
	 	 	Name:
	 	 	Title:




 


This
is one of the Notes referred to

in the within-mentioned Indenture:


 


Wilmington
Savings Fund Society, FSB

as Trustee


 





	By:	 	 
	Authorized
    Signatory	 







     


     


    



[Back
of Note]

9.125% Senior Notes due 2021


 


[Insert
the Global Note Legend, if applicable pursuant to the provisions of the Indenture]


 


[Insert
the Private Placement Legend, if applicable pursuant to the provisions of the Indenture]


 


Capitalized
terms used herein have the meanings assigned to them in the Indenture referred to below unless otherwise indicated.


 


(i)           INTEREST.
ION Geophysical Corporation, a Delaware corporation (the “Company”), promises to pay or cause to be paid interest
on the principal amount of this Note at 9.125% per annum from April 20, 2021 until maturity. The Company will pay interest annually
in arrears on June 15 and December 15 of each year, except that the interest payment otherwise payable on June 15, 2021 will be
payable on December 15, 2021, or if any such day is not a Business Day, on the next succeeding Business Day (each, an “Interest
Payment Date”). Interest on the Notes will accrue from the most recent date to which interest has been paid or, if no
interest has been paid, from the date of issuance; provided that, if this Note is authenticated between a record date referred
to on the face hereof and the next succeeding Interest Payment Date, interest shall accrue from such next succeeding Interest
Payment Date; provided further that the first Interest Payment Date shall be June 15, 2021. The Company will pay interest
(including post-petition interest in any proceeding under any Bankruptcy Law) on overdue principal at a rate that is 1% higher
than the then applicable interest rate on the Notes to the extent lawful; it will pay interest (including post-petition interest
in any proceeding under any Bankruptcy Law) on overdue installments of (without regard to any applicable grace period), at the
same rate to the extent lawful.


 


Interest
will be computed on the basis of a 360-day year comprised of twelve 30-day months.


 


METHOD
OF PAYMENT. The Company will pay interest on the Notes (except defaulted interest) to the Persons who are registered Holders
of Notes at the close of business on the June 1 and December 1 next preceding the Interest Payment Date, even if such Notes are
canceled after such record date and on or before such Interest Payment Date, except as provided in Section 2.12 of the Indenture
with respect to defaulted interest. The Notes will be payable as to principal, premium, if any, and interest, if any, at the office
or agency of the Paying Agent and Registrar within the City and State of New York, or, at the option of the Company, payment of
interest, if any, may be made by check mailed to the Holders at their addresses set forth in the register of Holders; provided
that payment by wire transfer of immediately available funds will be required with respect to principal of, premium on, if
any, and interest, if any, on, all Global Notes and all other Notes the Holders of which will have provided wire transfer instructions
to the Company or the Paying Agent. Such payment will be in such coin or currency of the United States of America as at the time
of payment is legal tender for payment of public and private debts.


 


(ii)          PAYING
AGENT AND REGISTRAR. Initially, Wilmington Savings Fund Society, FSB, the Trustee under the Indenture, will act as Paying Agent
and Registrar. The Company may change the Paying Agent or Registrar without prior notice to the Holders of the Notes. The Company
or any of its Subsidiaries may act as Paying Agent or Registrar.


 


(iii)         INDENTURE.
The Company has issued the Notes under an Indenture dated as of April 28, 2016 (as amended, modified and supplemented from time
to time, the “Indenture”) among the Company, the Guarantors and the Trustee and the Collateral Agent. The terms of
the Notes include those stated in the Indenture and those made part of the Indenture by reference to the TIA. The Notes are subject
to all such terms, and Holders are referred to the Indenture and the TIA for a statement of such terms. To the extent any provision
of this Note conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling.
The Indenture does not limit the aggregate principal amount of Notes that may be issued thereunder.


 


(iv)         MANDATORY
REDEMPTION. The Company is not required to make mandatory redemption or sinking fund payments with respect to the Notes.





     


     


    



(v)          REPURCHASE
AT THE OPTION OF HOLDER. Upon the occurrence of a Change of Control, the Company will be required to make an offer (a “Change
of Control Offer”) to each Holder to repurchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess
thereof) of that Holder’s Notes at a purchase price in cash equal to 101% of the aggregate principal amount of Notes repurchased,
plus accrued and unpaid interest, if any, on the Notes repurchased to the date of purchase, subject to the rights of Holders of
Notes on the relevant record date to receive interest due on the relevant interest payment date (the “Change of Control
Payment”). Within ten days following any Change of Control, the Company will mail a notice to each Holder setting forth
the procedures governing the Change of Control Offer as required by the Indenture.


 


NOTICE
OF REDEMPTION. At least 30 days but not more than 60 days before a redemption date, the Company will mail or cause to be mailed,
by first class mail, a notice of redemption to each Holder whose Notes are to be redeemed at its registered address, except that
redemption notices may be mailed more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance
of the Notes or a satisfaction and discharge of the Indenture pursuant to Articles 8 or 12 thereof.


 


Notes
and portions of Notes selected will be in amounts of $2,000 or whole multiples of $1,000 in excess thereof; except that if all
of the Notes of a Holder are to be redeemed or purchased, the entire outstanding amount of Notes held by such Holder shall be
redeemed or purchased. Notice of any redemption, including, without limitation, upon an Equity Offering, may, at the Company’s
discretion, be subject to one or more conditions precedent, including, but not limited to, completion of the related Equity Offering.


 


(vi)         DENOMINATIONS,
TRANSFER, EXCHANGE. The Notes are in registered form in minimum denominations of $2,000 and integral multiples of $1,000 in excess
thereof. The transfer of Notes may be registered and Notes may be exchanged as provided in the Indenture. The Registrar and the
Trustee may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and the Company may
require a Holder to pay any taxes and fees required by law or permitted by the Indenture. The Company need not exchange or register
the transfer of any Note or portion of a Note selected for redemption, except for the unredeemed portion of any Note being redeemed
in part. Also, the Company need not exchange or register the transfer of any Notes for a period of 15 days before a selection
of Notes to be redeemed or during the period between a record date and the next succeeding Interest Payment Date.


 


(vii)        PERSONS
DEEMED OWNERS. The registered Holder of a Note may be treated as the owner of it for all purposes. Only registered Holders have
rights under the Indenture.


 


AMENDMENT,
SUPPLEMENT AND WAIVER. Subject to certain exceptions, the Indenture, the Notes, the Note Guarantees or any other Note Documents
may be amended or supplemented with the consent of the Holders of at least a majority in aggregate principal amount of the then
outstanding Notes including Additional Notes, if any, voting as a single class, and any existing Default or Event of Default or
compliance with any provision of the Indenture or the Notes or the Note Guarantees may be waived with the consent of the Holders
of a majority in aggregate principal amount of the then outstanding Notes including Additional Notes, if any, voting as a single
class. Without the consent of any Holder of Notes, the Indenture, the Notes, the Note Guarantees or any other Note Documents may
be amended or supplemented to cure any ambiguity, defect or inconsistency, to provide for uncertificated Notes in addition to
or in place of certificated Notes, to provide for the assumption of the Company’s or a Guarantor’s obligations to
Holders of the Notes and Note Guarantees by a successor to the Company or such Guarantor pursuant to the Indenture, to make any
change that would provide any additional rights or benefits to the Holders of the Notes or that does not adversely affect the
legal rights under the Indenture of any Holder, to comply with the requirements of the SEC in order to effect or maintain the
qualification of the Indenture under the TIA, to conform the text of the Indenture, the Notes, or the Note Guarantees the Security
Documents to any provision of the “Description of Notes” section of the Company’s registration statement on
Form S-4 dated January 29, 2021, as amended, relating to the initial offering of the Notes, to the extent that such provision
in that “Description of Notes” was intended to be a verbatim recitation of a provision of the Indenture, the Notes,
or the Note Guarantees or the Security Documents, which intent shall be evidenced by an Officers’ Certificate to that effect,
to enter into additional or supplemental security documents, to make, complete or confirm any grant of Collateral permitted or
required by the Indenture or any of the Security Documents or any release of Collateral that becomes effective as set forth in
the Indenture or any of the Security Documents, to provide for the issuance of Additional Notes in accordance with the limitations
set forth in the Indenture, or to allow any Guarantor to execute a supplemental indenture to the Indenture and/or a Note Guarantee
with respect to the Notes.





     


     


    



DEFAULTS
AND REMEDIES. Events of Default include: (a) default for 30 days in the payment when due of interest, if any, on, the Notes;
(b) default in the payment when due (at maturity, upon redemption or otherwise) of the principal of, or premium on, if any, the
Notes, (c) failure by the Company or any of its Restricted Subsidiaries to comply with the provisions of Section 5.01 of the Indenture;
(d) (1) failure by the Company or any of its Restricted Subsidiaries for 60 days after notice to the Company by the Trustee or
the Holders of at least 25% in aggregate principal amount of the Notes then outstanding voting as a single class to comply with
any of the other agreements in the Indenture or the Security Documents, or (2) failure by the Company for 180 days after notice
from the Trustee or Holders of at least 25% in aggregate principal amount of the Notes then outstanding to comply with the provisions
of Section 4.03 of the Indenture; (e) [intentionally omitted]; (f) [intentionally omitted]; (g) [intentionally omitted]; (h) except
as permitted by the Indenture, any Note Guarantee is held in any judicial proceeding to be unenforceable or invalid or ceases
for any reason to be in full force and effect, or any Guarantor, or any Person acting on behalf of any Guarantor, denies or disaffirms
its obligations under its Note Guarantee; and (i) certain events of bankruptcy or insolvency with respect to the Company or any
of its Restricted Subsidiaries that is a Significant Subsidiary or any group of Restricted Subsidiaries that, taken together,
would constitute a Significant Subsidiary. In the case of an Event of Default arising from certain events of bankruptcy or insolvency
with respect to the Company, any Restricted Subsidiary of the Company that is a Significant Subsidiary or any group of Restricted
Subsidiaries of the Company that, taken together, would constitute a Significant Subsidiary, all outstanding Notes will become
due and payable immediately without further action or notice. If any other Event of Default occurs and is continuing, the Trustee
or the Holders of at least 25% in aggregate principal amount of the then outstanding Notes may declare all the Notes to be due
and payable immediately. Holders may not enforce the Indenture or the Notes except as provided in the Indenture. Subject to certain
limitations, Holders of a majority in aggregate principal amount of the then outstanding Notes may direct the time, method and
place of conducting any proceeding for exercising any remedy available to the Trustee or exercising any trust or power conferred
on it. The Trustee may withhold from Holders of the Notes notice of any continuing Default or Event of Default (except a Default
or Event of Default relating to the payment of principal, premium, if any, or interest, if any,) if it determines that withholding
notice is in their interest. The Holders of a majority in aggregate principal amount of the then outstanding Notes by notice to
the Trustee may, on behalf of all the Holders of Notes, rescind an acceleration or waive an existing Default or Event of Default
and its respective consequences under the Indenture except a continuing Default or Event of Default in the payment of principal
of, premium on, if any, or interest, if any, on, the Notes (including in connection with an offer to purchase).


 


(viii)       TRUSTEE
DEALINGS WITH COMPANY. The Trustee, in its individual or any other capacity, may make loans to, accept deposits from, and perform
services for the Company or its Affiliates, and may otherwise deal with the Company or its Affiliates, as if it were not the Trustee.


 


(ix)          NO
RECOURSE AGAINST OTHERS. No director, officer, employee, incorporator or other owner of Capital Stock of the Company or any Guarantor,
as such, will have any liability for any obligations of the Company or the Guarantors under the Notes, the Indenture, the Note
Guarantees, the Note Documents or for any claim based on, in respect of, or by reason of, such obligations or their creation.
Each Holder of Notes by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration
for issuance of the Notes. The waiver may not be effective to waive liabilities under the federal securities laws.


 


(xi)          AUTHENTICATION.
This Note will not be valid until authenticated by the manual signature of the Trustee or an authenticating agent.


 


(xi)          ABBREVIATIONS.
Customary abbreviations may be used in the name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (=
tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian),
and U/G/M/A (= Uniform Gifts to Minors Act).





     


     


    



CUSIP
NUMBERS. Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company
has caused CUSIP numbers to be printed on the Notes, and the Trustee may use CUSIP numbers in notices of redemption as a convenience
to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any
notice of redemption, and reliance may be placed only on the other identification numbers placed thereon.


 


(xii)
         The parties hereto and each Holder hereby irrevocably submit to the nonexclusive jurisdiction of any New York State or Federal
court sitting in the Borough of Manhattan in the City of New York in any proceeding arising out of or relating to this Indenture,
the Note and the Note Guarantees and the parties and each Holder hereby irrevocably agree that all claims in respect of any such
proceeding may be heard and determined in any such New York State or federal court. The parties and each Holder hereby irrevocably
waive, to the fullest extent that they may legally do so, the defense of an inconvenient forum to the maintenance of such proceeding.
The parties and each Holder irrevocably consent to the service of process in any proceeding by the mailing or delivery of copies
of such process as set forth in Section 13.02 hereof. The parties and each Holder agree that a final non-appealable judgment in
any such proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner
provided by law.


 


(xiii)
        EACH PARTY AND EACH HOLDER HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT THAT
IT MAY HAVE TO A TRIAL BY JURY (BUT NO OTHER JUDICIAL REMEDIES) IN RESPECT OF ANY PROCEEDING ARISING OUT OF OR RELATING TO THIS
INDENTURE, THE NOTE AND THE NOTE GUARANTEES AND THE TRANSACTIONS CONTEMPLATED HEREBY.


 


(xiv)       GOVERNING
LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL GOVERN AND BE USED TO CONSTRUE THE INDENTURE, THIS NOTE AND THE NOTE GUARANTEES
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION
WOULD BE REQUIRED THEREBY.


 


The
Company will furnish to any Holder upon written request and without charge a copy of the Indenture. Requests may be made to:


 


ION
Geophysical Corporation

2105 CityWest Boulevard, Suite 100

Houston, Texas 77042

Facsimile: 281-879-3600

Attention: General Counsel





     


     


    



Assignment
Form


 


To
assign this Note, fill in the form below:


 


(I)
or (we) assign and transfer this Note to: ____


 


(Insert
assignee’s legal name)


 


(Insert
assignee’s soc. sec. or tax I.D. no.)


 


(Print
or type assignee’s name, address and zip code)


 


and
irrevocably appoint ____


 


to
transfer this Note on the books of the Company. The agent may substitute another to act for him.


 


Date:
_____________


 





	 	Your Signature: 	 
	 	(Sign exactly as your name appears on the face of this Note)




 


Signature
Guarantee*: ________________________________


 


*       Participant
in a recognized Signature Guarantee Medallion Program (or other signature guarantor acceptable to the Trustee).





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