Document:

EXHIBIT 4.2
                                                                    -----------

===============================================================================

                            DATED AS OF MAY 4, 2007

                                   NEXEN INC.

                                      AND

                      DEUTSCHE BANK TRUST COMPANY AMERICAS

                          FIRST SUPPLEMENTAL INDENTURE

                                     TO THE

                                TRUST INDENTURE

                            DATED AS OF MAY 4, 2007

===============================================================================

<PAGE>

THIS FIRST SUPPLEMENTAL  INDENTURE (this "FIRST SUPPLEMENTAL  INDENTURE") dated
as of May 4, 2007 between  NEXEN INC.,  a  corporation  incorporated  under the
Canada  Business  Corporations  Act and having  its head  office in the City of
Calgary,  in the Province of Alberta  (the  "ISSUER")  and DEUTSCHE  BANK TRUST
COMPANY AMERICAS,  a banking  corporation duly organized and existing under the
laws of the State of New York, having an office in the City of New York, in the
State of New York (the "Trustee")

                            RECITALS OF THE COMPANY

WHEREAS, the Issuer and the Trustee entered into an Indenture,  dated as of May
4, 2007 (the  "ORIGINAL  INDENTURE").  Section 9.01 of the  Original  Indenture
provides  that the Issuer  and the  Trustee  may,  without  the  consent of any
Holder,  enter into a supplemental  indenture to establish the form or terms of
Securities of any series as permitted by Section 2.01 and 3.01 thereof.

WHEREAS,  pursuant to Sections  2.01 and 3.01 of the  Original  Indenture,  the
Issuer desires to provide for the establishment of a series of Securities under
the Original  Indenture,  and the form and terms thereof,  as  hereinafter  set
forth.

WHEREAS,  the Issuer has  requested  that the Trustee  execute and deliver this
First  Supplemental  Indenture.  The Issuer  has  delivered  to the  Trustee an
Opinion of Counsel and an Officers' Certificate pursuant to Sections 1.02, 3.03
and 9.03 of the Original Indenture to the effect,  among other things, that all
conditions  precedent provided for in the Indenture to the Trustee's  execution
and delivery of this First Supplemental  Indenture have been complied with. All
acts and  things  necessary  have been done and  performed  to make this  First
Supplemental  Indenture  enforceable  in  accordance  with its  terms,  and the
execution  and  delivery  of this First  Supplemental  Indenture  has been duly
authorized in all respects.

         WHEREAS the proper  officers of the Issuer  have duly  authorized  the
creation and issuance of: (i) a series of  Securities to be designated as 5.65%
Notes due 2017 (the "2017 NOTES") and to be initially  limited  (subject to the
exceptions  described  herein and in the Original  Indenture)  to the aggregate
principal  amount of  U.S.$250,000,000;  and (ii) a series of  Securities to be
designated  as 6.40% Notes due 2037 (the "2037  NOTES" and,  together  with the
2017 Notes, the "NOTES") and to be initially limited (subject to the exceptions
described  herein and in the Original  Indenture)  to the  aggregate  principal
amount of  U.S.$1,250,000,000;  the further terms and conditions  thereof being
hereinafter set forth,  all in accordance with a resolution of the directors of
the Issuer;

         NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH:  For and
in  consideration of the premises and the purchase of the Securities (as herein
defined) by the holders thereof,  it is mutually covenanted and agreed, for the
equal and proportionate benefit of all holders of the Securities, as follows:

<PAGE>
                                      -2-

1.       INTERPRETATIONS AND AMENDMENTS

1.1      FIRST SUPPLEMENTAL INDENTURE

         As used herein "FIRST  SUPPLEMENTAL  INDENTURE",  "HERETO",  "HEREIN",
"HEREOF",  "HEREBY",  "HEREUNDER" and similar  expressions  refer to this First
Supplemental  Indenture  and not to any  particular  Article,  Section or other
portion hereof and include any and every  instrument  supplemental or ancillary
hereto or in implementation  hereof, and further include the terms of the Notes
set forth in the form of 2017 Notes  annexed as  Schedule A hereto and the form
of 2037 Notes annexed as Schedule B hereto.

1.2      DEFINITIONS IN FIRST SUPPLEMENTAL INDENTURE

         All terms  contained in this First  Supplemental  Indenture  which are
defined  in the  Original  Indenture  and not  defined  herein  shall,  for all
purposes  hereof,  have  the  meanings  given  to such  terms  in the  Original
Indenture,  unless the  context  otherwise  specifies  or  requires;  provided,
however,  that notwithstanding the foregoing,  the terms "ISSUER" and "TRUSTEE"
shall have the respective meanings given to them in the Original Indenture.

1.3      INTERPRETATION NOT AFFECTED BY HEADINGS

         The division of this First  Supplemental  Indenture  into Articles and
Sections,  the  provision of the table of contents  hereto and the insertion of
headings  are for  convenience  of  reference  only and  shall not  affect  the
construction or interpretation of this First Supplemental Indenture.

2.       NOTES

2.1      FORM AND TERMS OF NOTES

         There  shall be and there is hereby  created  for  issuance  under the
Original Indenture, as supplemented by this First Supplemental Indenture; (i) a
series of Securities  which shall consist of an aggregate  principal  amount of
U.S.$250,000,000  2017  Notes;  and (ii) a series  of  Securities  which  shall
consist  of an  aggregate  principal  amount of  U.S.$1,250,000,000  2037 Notes
provided, however, that if the Issuer shall, at any time after the date hereof,
increase  the  principal  amount of either or both series of Notes which may be
issued and issue such increased principal amount (or any portion thereof), then
any such  additional  Notes so issued shall have the same form and terms (other
than the date of issuance and the date from which interest  thereon shall begin
to accrue and, under certain  circumstances,  the first interest payment date),
and shall carry the same right to receive accrued and unpaid  interest,  as the
Notes theretofore  issued; and provided,  further,  that,  notwithstanding  the
foregoing, the Issuer shall not be entitled to increase the principal amount of
Notes which may be issued or issue any such increased  principal  amount if the
Issuer has effected  satisfaction  and discharge of the  Indenture  pursuant to
Section 4.01 of the Original  Indenture or  defeasance  or covenant  defeasance
pursuant to Article 13 of the Original Indenture.

         The 2017 Notes will  mature,  and the  principal of the 2017 Notes and
accrued and unpaid interest  thereon will be due and payable,  on May 15, 2017,
or such earlier date as the principal of

<PAGE>
                                      -3-

any of the 2017  Notes  may  become  due and  payable  in  accordance  with the
provisions of the Original Indenture and this First Supplemental Indenture.

         The 2037 Notes will  mature,  and the  principal of the 2037 Notes and
accrued and unpaid interest  thereon will be due and payable,  on May 15, 2037,
or such earlier  date as the  principal of any of the 2037 Notes may become due
and payable in accordance with the provisions of the Original Indenture and the
First Supplemental Indenture.

         The Notes shall bear interest on the principal amount thereof from May
4, 2007 or from the last date to which  interest  shall  have been paid or duly
made  available  for payment on the Notes,  whichever is later,  at the rate of
5.65%  per  annum in the case of the 2017  Notes  and at the rate of 6.40%  per
annum in the case of the 2037  Notes,  in each case  payable  semi-annually  in
arrears on May 15 and November 15 (each,  an "INTEREST  PAYMENT  DATE") in each
year, commencing November 15, 2007, until the principal of and premium, if any,
on the  applicable  series of Notes is paid or duly made available for payment;
and should the Issuer at any time default in the payment of any  principal  of,
or premium,  if any, or  interest on either  series of the Notes when due,  the
Issuer  shall pay  interest  (such  interest to be payable on  demand),  to the
extent  permitted by law, on the amount in default at the same rate  applicable
to such  series of Notes.  Interest on the Notes shall be computed on the basis
of a 360-day year comprised of twelve 30-day months. The interest payable,  and
punctually  paid or duly  provided  for, on any Interest  Payment Date will, as
provided in the Original  Indenture,  be paid to the Persons in whose names the
Notes  (or one or more  predecessor  Notes)  are  registered  at the  close  of
business on May 1 or November 1 (the "REGULAR RECORD  DATES"),  as the case may
be, immediately prior to such Interest Payment Date,  regardless of whether any
such Regular  Record Date is a business day. Any such interest on the Notes not
so punctually  paid or duly provided for on any Interest  Payment Date shall be
payable,  as  applicable,  as provided in the forms of Notes annexed  hereto as
Schedule A and Schedule B to this First Supplemental Indenture.

         For the purposes only of the  disclosure  required by the INTEREST ACT
(Canada), and without affecting the amount of interest payable to any holder of
a Note or the  calculation  of interest on any Note, if the rate of interest on
any  Note is  calculated  on the  basis of a year  (the  "DEEMED  year")  which
contains  fewer days than the  actual  number of days in the  calendar  year of
calculation,  such rate of interest shall be expressed as a yearly rate for the
purposes of the INTEREST ACT (Canada) by  multiplying  such rate of interest by
the actual number of days in the calendar year of  calculation  and dividing it
by the number of days in the deemed year.

         All payments of principal of and premium,  if any, and interest on the
Notes will be made 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,
and all references herein to "UNITED STATES DOLLARS", "U.S.$" or "U.S. DOLLARS"
shall be deemed  to refer to such  coin or  currency  of the  United  States of
America.

         The principal of and premium,  if any, and interest on the Notes shall
be  payable,  and the  Notes may be  surrendered  for  exchange,  registration,
transfer or discharge from  registration,  at the Corporate Trust Office of the
Trustee  in the City of New York,  New York,  and in such  other  places as the
Issuer  may  from  time to time  designate  in  accordance  with  the  Original
Indenture.

<PAGE>
                                      -4-

The Trustee is hereby  appointed as the initial  Paying  Agent,  registrar  and
transfer agent for the Notes in the City of New York, New York.

         The Notes  shall be issued  only as fully  registered  Notes,  without
coupons,  in  denominations  of  U.S.$2,000  and  integral  multiples of $1,000
thereafter.  Each series of Notes  initially will be represented by one or more
global Securities (collectively,  the "GLOBAL NOTES") registered in the name of
The  Depository  Trust  Company,  as Depositary or its nominee,  or a successor
depositary or its nominee.

         The  certificates  representing  the Notes  shall  bear the  following
legend:

         "THIS  SECURITY  IS IN GLOBAL  FORM WITHIN THE MEANING OF THE
         TRUST INDENTURE  HEREINAFTER REFERRED TO AND IS REGISTERED IN
         THE NAME OF THE  DEPOSITARY  OR A NOMINEE OF THE  DEPOSITARY.
         UNLESS  AND  UNTIL  IT IS  EXCHANGED  IN WHOLE OR IN PART FOR
         SECURITIES IN CERTIFICATED FORM IN THE LIMITED  CIRCUMSTANCES
         DESCRIBED  IN  THE  INDENTURE,   THIS  SECURITY  MAY  NOT  BE
         TRANSFERRED  EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE
         OF THE  DEPOSITARY  OR BY A NOMINEE OF THE  DEPOSITARY TO THE
         DEPOSITARY  OR ANOTHER  NOMINEE OF THE  DEPOSITARY  OR BY THE
         DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A
         NOMINEE OF SUCH SUCCESSOR DEPOSITARY."

         The Notes and the certificate of the Trustee endorsed thereon shall be
in the form set out in Schedule A, in the case of the 2017 Notes,  and Schedule
B, in the case of the 2037 Notes,  to this First  Supplemental  Indenture  with
such appropriate  insertions,  omissions,  substitutions  and variations as the
Trustee  may  approve  and shall be  numbered in such manner as the Trustee may
approve,  such approvals of the Trustee  concerning any Note to be conclusively
evidenced by its certification of such Note.

         The  Security  Register  referred to in Section  3.05 of the  Original
Indenture shall,  with respect to the Notes, be kept at the office or agency in
the City of New York,  New York that the Issuer may from time to time designate
for such purpose  (which shall  initially be the Corporate  Trust Office of the
Trustee in the City of New York,  New York),  and at such other place or places
as the Issuer with the approval of the Trustee may hereafter designate.

         The Notes shall be subject to  redemption  at the option of the Issuer
as provided in Article 3 of this First Supplemental Indenture. The Issuer shall
not be required to redeem,  purchase or repay Notes  pursuant to any  mandatory
redemption, sinking fund or analogous provision or at the option of the holders
thereof.  The Notes will not be convertible into or exchangeable for securities
of any Person.

         The Notes shall have the other terms and  provisions  set forth in the
forms of  Notes  attached  hereto  as  Schedule  A to this  First  Supplemental
Indenture,  in the  case of the  2017  Notes,  and  Schedule  B to  this  First
Supplemental  Indenture, in the case of the 2037 Notes, with the same force and
effect as if such terms and provisions were set forth in full herein.

<PAGE>
                                      -5-

2.2      ISSUANCE OF NOTES

         2017 Notes in the aggregate principal amount of  U.S.$250,000,000  and
2037 Notes in the aggregate  principal  amount of  U.S.$1,250,000,000  shall be
executed by the Designated Officer of the Issuer and delivered by the Issuer to
the Trustee on the date of issue for  authentication  and delivery  pursuant to
and in accordance with the provisions of Section 3.03 of the Original Indenture
and, upon the  requirements of such  provisions  being complied with, the Notes
shall be authenticated by or on behalf of the Trustee and delivered by it to or
upon the Issuer Order of the Issuer without any further act or formality on the
part of the  Issuer.  The  Trustee  shall have no duty or  responsibility  with
respect  to the  use or  application  of any of  the  Notes  so  certified  and
delivered or the proceeds thereof.

3.       REDEMPTION OF NOTES

3.1      REDEMPTION OF NOTES

         Each series of the Notes will be  redeemable  at any time, in whole or
from time to time in part,  at the  option of the  Issuer (in the manner and in
accordance with and subject to the terms and provisions set forth in Article 11
of the Original Indenture), at a Redemption Price equal to the greater of:

         (a)      100% of the principal amount of the Notes to be redeemed; and

         (b)      the sum of the  present  values  of the  remaining  scheduled
                  payments of principal  and  interest  thereon  (exclusive  of
                  interest accrued to the date of redemption) discounted to the
                  Redemption  Date on a semi-annual  basis  (assuming a 360-day
                  year  consisting  of twelve  30-day  months) at the  Treasury
                  Rate, plus 20 basis points in the case of the 2017 Notes, and
                  plus 35 basis points in the case of the 2037 Notes;

plus in each case  accrued  interest  to the  Redemption  Date;  provided  that
installments of interest on Notes which are due and payable on any date falling
on or prior to a Redemption  Date will be payable to the registered  holders of
such Notes (or one or more  predecessor  Notes),  registered  as such as of the
close of business on the relevant Regular Record Dates.

         The Issuer will provide  notice to the Trustee prior to the Redemption
Date of the calculation of the Redemption Price.

3.2      ADDITIONAL DEFINITIONS

         For the purposes of this First Supplemental  Indenture,  the following
expressions shall have the following meanings:

         "COMPARABLE  TREASURY ISSUE" means the U.S. Treasury security selected
by an  Independent  Investment  Banker as having a maturity  comparable  to the
remaining term of the  applicable  series of Notes to be redeemed that would be
utilized,  at the time of selection and in accordance with customary  financial
practice,  in pricing new issues of corporate  debt  securities  of  comparable
maturity to the remaining term of such Notes;

<PAGE>
                                      -6-

         "COMPARABLE  TREASURY  PRICE"  means,  with respect to any  redemption
date, (i) the average of the bid and asked prices for the  Comparable  Treasury
Issue  (expressed in each case as a percentage of its principal  amount) on the
third  business day preceding such  redemption  date, as set forth in the daily
statistical release (or any successor release) published by the Federal Reserve
Bank of New  York and  designated  "COMPOSITE  3:30  P.M.  QUOTATIONS  FOR U.S.
GOVERNMENT  SECURITIES"  or (ii) if such release (or any successor  release) is
not  published  or does not contain such prices on such  business  day, (A) the
average of the Reference  Treasury Dealer  Quotations for such redemption date,
after  excluding  the  highest  and  lowest  such  Reference   Treasury  Dealer
Quotations,  or (B) if the  Issuer  is unable  to  obtain  four such  Reference
Treasury Dealer Quotations, the average of all such Quotations;

         "INDEPENDENT  INVESTMENT  BANKER" means one of the  Reference  Dealers
selected by the Issuer;

         "REFERENCE  DEALER"  means  each of Banc of  America  Securities  LLC,
Citigroup  Global  Markets  Inc. and Deutsche  Bank  Securities  Inc. and their
respective  successors,  and two other firms that are primary  U.S.  government
securities  dealers in the City of New York (each a "PRIMARY  TREASURY Dealer")
which the Issuer specifies from time to time; provided, however, that if any of
the foregoing  Reference  Dealers shall cease to be a Primary  Treasury Dealer,
the Issuer shall substitute therefor another Primary Treasury Dealer;

         "REFERENCE  TREASURY DEALER  QUOTATIONS"  means,  with respect to each
Reference  Dealer and any redemption  date,  the average,  as determined by the
Issuer,  of the  bid  and  asked  prices  for  the  Comparable  Treasury  Issue
(expressed  in each case as a percentage  of its  principal  amount)  quoted in
writing  to the  Issuer by such  Reference  Dealer at 3:30 p.m.  (New York City
time) on the third business day preceding such redemption date; and

         "TREASURY RATE" means,  with respect to any redemption  date, the rate
per  year  equal  to  the  semi-annual  equivalent  yield  to  maturity  of the
Comparable  Treasury Issue,  assuming a price for the Comparable Treasury Issue
(expressed  as a percentage of its  principal  amount) equal to the  Comparable
Treasury Price for such redemption date.

4.       GENERAL

4.1      EFFECTIVENESS

         This First  Supplemental  Indenture  will  become  effective  upon its
execution and delivery.

4.2      EFFECT OF RECITALS

         The  recitals  contained  herein  and in the  Securities,  except  the
Trustee's  certificates of authentication,  shall be taken as the statements of
the Issuer,  and neither the Trustee nor any  Authenticating  Agent assumes any
responsibility   for  their   correctness.   Neither   the   Trustee   nor  any
Authenticating  Agent shall be  accountable  for the use or  application by the
Issuer  of the  Securities  or the  proceeds  thereof.  The  Trustee  makes  no
representations  as to the validity or sufficiency  of this First  Supplemental
Indenture or of the Securities  except that the Trustee  represents  that it is
duly  authorized  to execute and  deliver  this First  Supplemental  Indenture,
authenticate  the  Securities  and perform its  obligations  under the Original
Indenture and

<PAGE>
                                      -7-

hereunder,  and  that  the  statements  made  by it or  to be  made  by it in a
Statement of Eligibility and  Qualification  on Form T-1 supplied to the Issuer
are true and accurate.

4.3      RATIFICATION OF ORIGINAL INDENTURE

         The Original  Indenture  as  supplemented  by this First  Supplemental
Indenture  is  in  all  respects   ratified  and  confirmed,   and  this  First
Supplemental  Indenture  shall be deemed part of the Original  Indenture in the
manner and to the extent herein and therein provided.

4.4      GOVERNING LAW

         This  First   Supplemental   Indenture,   the  Original  Indenture  as
supplemented  hereby and the  Securities  shall be governed by and construed in
accordance with the laws of the State of New York.

4.5      SEVERABILITY

         In case  any  provision  in this  First  Supplemental  Indenture,  the
Original  Indenture  as  supplemented  hereby  or in the  Securities  shall  be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

4.6      ACCEPTANCE OF TRUST

         The  Trustee  hereby  accepts  the trusts in this  First  Supplemental
Indenture  declared  and  provided  for and agrees to perform the same upon the
terms and conditions  herein before set forth in trust for the various  Persons
who  shall  from  time to time be Note  holders  subject  to all the  terms and
conditions herein set forth.

4.7      COUNTERPARTS AND FORMAL DATE

         This First  Supplemental  Indenture  may be  executed in any number of
counterparts,  each of which so executed shall be deemed to be an original, but
all such counterparts shall together constitute but one and the same instrument
and  notwithstanding  their date of execution  shall be deemed to bear the date
first above written.

<PAGE>

         IN WITNESS WHEREOF the parties hereto have executed this  Supplemental
Indenture on the date first above written.

                                      NEXEN INC.

                                      Per:   /s/ Marvin F. Romanow
                                             ---------------------------------
                                             Marvin F. Romanow
                                             Executive Vice President and
                                             Chief Financial Officer

                                      Per:   /s/ Una M. Power
                                             ---------------------------------
                                             Una M. Power
                                             Treasurer

                                      DEUTSCHE BANK TRUST COMPANY
                                      AMERICAS, as trustee

                                      By Deutsche Bank National Trust Company

                                      Per:   /s/ Yana Kalachikova
                                             ---------------------------------
                                             Name: Yana Kalachikova
                                             Title: Assistant Vice President

                                      Per:   /s/ Rodney Gaughan
                                             ---------------------------------
                                             Name: Rodney Gaughan
                                             Title: Vice President

<PAGE>

                               TABLE OF CONTENTS

1.    INTERPRETATIONS AND AMENDMENTS..........................................2

      1.1   FIRST SUPPLEMENTAL INDENTURE......................................2
      1.2   DEFINITIONS IN FIRST SUPPLEMENTAL INDENTURE.......................2
      1.3   INTERPRETATION NOT AFFECTED BY HEADINGS...........................2

2.    NOTES...................................................................2

      2.1   FORM AND TERMS OF NOTES...........................................2
      2.2   ISSUANCE OF NOTES.................................................5

3.    REDEMPTION OF NOTES.....................................................5

      3.1   REDEMPTION OF NOTES...............................................5
      3.2   ADDITIONAL DEFINITIONS............................................5

4.    GENERAL.................................................................6

      4.1   EFFECTIVENESS.....................................................6
      4.2   EFFECT OF RECITALS................................................6
      4.3   RATIFICATION OF ORIGINAL INDENTURE................................7
      4.4   GOVERNING LAW.....................................................7
      4.5   SEVERABILITY......................................................7
      4.6   ACCEPTANCE OF TRUST...............................................7
      4.7   COUNTERPARTS AND FORMAL DATE......................................7Exhibit 4.3 
 Dated as of July 30, 2009 
 NEXEN INC. 
 and 
 DEUTSCHE BANK TRUST COMPANY AMERICAS 
 SECOND SUPPLEMENTAL INDENTURE 
 to
the 
 TRUST INDENTURE 
 Dated as of May 4, 2007 

 THIS SECOND SUPPLEMENTAL INDENTURE (this “Second Supplemental Indenture”) dated as of July 30, 2009
between NEXEN INC., a corporation incorporated under the Canada Business Corporations Act and having its head office in the City of Calgary, in the Province of Alberta (the “Issuer”) and DEUTSCHE BANK TRUST COMPANY
AMERICAS, a banking corporation duly organized and existing under the laws of the State of New York, having an office in the City of New York, in the State of New York (the “Trustee”) 
 RECITALS OF THE COMPANY 
 WHEREAS, the Issuer
and the Trustee entered into an Indenture, dated as of May 4, 2007 (the “Original Indenture”). Section 9.01 of the Original Indenture provides that the Issuer and the Trustee may, without the consent of any Holder, enter
into a supplemental indenture to establish the form or terms of Securities of any series as permitted by Section 2.01 and 3.01 thereof. 
 WHEREAS, the Issuer and the Trustee entered into a First Supplemental Indenture dated as of May 4, 2007 providing for the issuance and creation of: (i) a series of Securities designated as 5.65% Notes due 2017; and
(ii) a series of Securities designated as 6.40% Notes due 2037. 
 WHEREAS, pursuant to Sections 2.01 and 3.01 of the Original Indenture, the
Issuer desires to provide for the establishment of a series of Securities under the Original Indenture, and the form and terms thereof, as hereinafter set forth. 
 WHEREAS, the Issuer has requested that the Trustee execute and deliver this Second Supplemental Indenture. The Issuer has delivered to the Trustee an Opinion of Counsel and an Officers’ Certificate pursuant to Sections 1.02,
3.03 and 9.03 of the Original Indenture to the effect, among other things, that all conditions precedent provided for in the Indenture to the Trustee’s execution and delivery of this Second Supplemental Indenture have been complied with. All
acts and things necessary have been done and performed to make this Second Supplemental Indenture enforceable in accordance with its terms, and the execution and delivery of this Second Supplemental Indenture has been duly authorized in all
respects. 
 WHEREAS the proper officers of the Issuer have duly authorized the creation and issuance of: (i) a series of
Securities to be designated as 6.20% Notes due 2019 (the “2019 Notes”) and to be initially limited (subject to the exceptions described herein and in the Original Indenture) to the aggregate principal amount of U.S.$300,000,000; and
(ii) a series of Securities to be designated as 7.50% Notes due 2039 (the “2039 Notes” and, together with the 2019 Notes, the “Notes”) and to be initially limited (subject to the exceptions described herein and
in the Original Indenture) to the aggregate principal amount of U.S.$700,000,000; the further terms and conditions thereof being hereinafter set forth, all in accordance with a resolution of the directors of the Issuer; 
 NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH: For and in consideration of the premises and the purchase of the Securities (as
herein defined) by the holders thereof, it is mutually covenanted and agreed, for the equal and proportionate benefit of all holders of the Securities, as follows: 

 -2- 
  

	1.	INTERPRETATIONS AND AMENDMENTS 

  

	1.1	Second Supplemental Indenture 

 As used herein
“Second Supplemental Indenture”, “hereto”, “herein”, “hereof”, “hereby”, “hereunder” and similar expressions refer to this Second Supplemental
Indenture and not to any particular Article, Section or other portion hereof and include any and every instrument supplemental or ancillary hereto or in implementation hereof, and further include the terms of the Notes set forth in the form of 2019
Notes annexed as Schedule A hereto and the form of 2039 Notes annexed as Schedule B hereto. 
  

	1.2	Definitions in Second Supplemental Indenture 

 All
terms contained in this Second Supplemental Indenture which are defined in the Original Indenture and not defined herein shall, for all purposes hereof, have the meanings given to such terms in the Original Indenture, unless the context otherwise
specifies or requires; provided, however, that notwithstanding the foregoing, the terms “Issuer” and “Trustee” shall have the respective meanings given to them in the Original Indenture. 
  

	1.3	Interpretation not Affected by Headings 

 The
division of this Second Supplemental Indenture into Articles and Sections, the provision of the table of contents hereto and the insertion of headings are for convenience of reference only and shall not affect the construction or interpretation of
this Second Supplemental Indenture. 
  

	2.	NOTES 

  

	2.1	Form and Terms of Notes 

 There shall be and there
is hereby created for issuance under the Original Indenture, as supplemented by this Second Supplemental Indenture; (i) a series of Securities which shall consist of an aggregate principal amount of U.S.$300,000,000 2019 Notes; and (ii) a
series of Securities which shall consist of an aggregate principal amount of U.S.$700,000,000 2039 Notes provided, however, that if the Issuer shall, at any time after the date hereof, increase the principal amount of either or both series of Notes
which may be issued and issue such increased principal amount (or any portion thereof), then any such additional Notes so issued shall have the same form and terms (other than the date of issuance and the date from which interest thereon shall begin
to accrue and, under certain circumstances, the first interest payment date), and shall carry the same right to receive accrued and unpaid interest, as the Notes theretofore issued; and provided, further, that, notwithstanding the foregoing, the
Issuer shall not be entitled to increase the principal amount of Notes which may be issued or issue any such increased principal amount if the Issuer has effected satisfaction and discharge of the Indenture pursuant to Section 4.01 of the
Original Indenture or defeasance or covenant defeasance pursuant to Article 13 of the Original Indenture. 
 The 2019 Notes will mature, and
the principal of the 2019 Notes and accrued and unpaid interest thereon will be due and payable, on July 30, 2019 or such earlier date as the principal of any of the 2019 Notes may become due and payable in accordance with the provisions of the
Original Indenture and this Second Supplemental Indenture. 

 -3- 
  

 The 2039 Notes will mature, and the principal of the 2039 Notes and accrued and unpaid interest thereon
will be due and payable, on July 30, 2039 or such earlier date as the principal of any of the 2039 Notes may become due and payable in accordance with the provisions of the Original Indenture and this Second Supplemental Indenture. 
 The Notes shall bear interest on the principal amount thereof from July 30, 2009 or from the last date to which interest shall have been paid or duly
made available for payment on the Notes, whichever is later, at the rate of 6.20% per annum in the case of the 2019 Notes and at the rate of 7.50% per annum in the case of the 2039 Notes, in each case payable semi-annually in arrears on
January 30 and July 30 (each, an “Interest Payment Date”) in each year, commencing January 30, 2010, until the principal of and premium, if any, on the applicable series of Notes is paid or duly made available for payment; and
should the Issuer at any time default in the payment of any principal of, or premium, if any, or interest on either series of the Notes when due, the Issuer shall pay interest (such interest to be payable on demand), to the extent permitted by law,
on the amount in default at the same rate applicable to such series of Notes. Interest on the Notes shall be computed on the basis of a 360-day year comprised of twelve 30-day months. The interest payable, and punctually paid or duly provided for,
on any Interest Payment Date will, as provided in the Original Indenture, be paid to the Persons in whose names the Notes (or one or more predecessor Notes) are registered at the close of business on January 15 or July 15 (the “Regular
Record Dates”), as the case may be, immediately prior to such Interest Payment Date, regardless of whether any such Regular Record Date is a business day. Any such interest on the Notes not so punctually paid or duly provided for on any
Interest Payment Date shall be payable, as applicable, as provided in the forms of Notes annexed hereto as Schedule A and Schedule B to this Second Supplemental Indenture. 
 For the purposes only of the disclosure required by the Interest Act (Canada), and without affecting the amount of interest payable to any holder
of a Note or the calculation of interest on any Note, if the rate of interest on any Note is calculated on the basis of a year (the “deemed year”) which contains fewer days than the actual number of days in the calendar year of
calculation, such rate of interest shall be expressed as a yearly rate for the purposes of the Interest Act (Canada) by multiplying such rate of interest by the actual number of days in the calendar year of calculation and dividing it by the
number of days in the deemed year. 
 All payments of principal of and premium, if any, and interest on the Notes will be made 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, and all references herein to “United States dollars”, “U.S.$” or “U.S.
dollars” shall be deemed to refer to such coin or currency of the United States of America. 
 The principal of and premium, if any,
and interest on the Notes shall be payable, and the Notes may be surrendered for exchange, registration, transfer or discharge from registration, at the Corporate Trust Office of the Trustee in the City of New York, New York, and in such other
places as the Issuer may from time to time designate in accordance with the Original Indenture. The Trustee is hereby appointed as the initial Paying Agent, registrar and transfer agent for the Notes in the City of New York, New York. 

 -4- 
  

 The Notes shall be issued only as fully registered Notes, without coupons, in minimum denominations of
U.S.$2,000 and integral multiples of $1,000 thereafter. Each series of Notes initially will be represented by one or more global Securities (collectively, the “Global Notes”) registered in the name of The Depository Trust Company,
as Depositary or its nominee, or a successor depositary or its nominee. 
 The certificates representing the Notes shall bear the following
legend: 
 “THIS SECURITY IS IN GLOBAL FORM WITHIN THE MEANING OF THE TRUST INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE
NAME OF THE DEPOSITARY OR A NOMINEE OF THE DEPOSITARY. UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN CERTIFICATED FORM IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE, THIS SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A
WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR
DEPOSITARY.” 
 The Notes and the certificate of the Trustee endorsed thereon shall be in the form set out in Schedule A, in the case of
the 2019 Notes, and Schedule B, in the case of the 2039 Notes, to this Second Supplemental Indenture with such appropriate insertions, omissions, substitutions and variations as the Trustee may approve and shall be numbered in such manner as the
Trustee may approve, such approvals of the Trustee concerning any Note to be conclusively evidenced by its certification of such Note. 
 The
Security Register referred to in Section 3.05 of the Original Indenture shall, with respect to the Notes, be kept at the office or agency in the City of New York, New York that the Issuer may from time to time designate for such purpose (which
shall initially be the Corporate Trust Office of the Trustee in the City of New York, New York), and at such other place or places as the Issuer with the approval of the Trustee may hereafter designate. 
 The Notes shall be subject to redemption at the option of the Issuer as provided in Article 3 of this Second Supplemental Indenture. The Issuer
shall not be required to redeem, purchase or repay Notes pursuant to any mandatory redemption, sinking fund or analogous provision or at the option of the holders thereof. The Notes will not be convertible into or exchangeable for securities of any
Person. 
 The Notes shall have the other terms and provisions set forth in the forms of Notes attached hereto as Schedule A to this Second
Supplemental Indenture, in the case of the 2019 Notes, and Schedule B to this Second Supplemental Indenture, in the case of the 2039 Notes, with the same force and effect as if such terms and provisions were set forth in full herein. 
  

	2.2	Issuance of Notes 

 2019 Notes in the aggregate
principal amount of U.S.$300,000,000 and 2039 Notes in the aggregate principal amount of U.S.$700,000,000 shall be executed by the Designated Officer of the Issuer and delivered by the Issuer to the Trustee on the date of issue for authentication
and delivery pursuant to and in accordance with the provisions of Section 3.03 of the Original Indenture and, upon the requirements of such provisions being complied with, the Notes shall be authenticated by or on behalf of the Trustee and
delivered by it to or upon the Issuer Order of the Issuer without any further act or formality on the part of the Issuer. The Trustee shall have no duty or responsibility with respect to the use or application of any of the Notes so certified and
delivered or the proceeds thereof. 

 -5- 
  

	3.	REDEMPTION OF NOTES 

  

	3.1	Redemption of Notes 

 Each series of the Notes will
be redeemable at any time, in whole or from time to time in part, at the option of the Issuer (in the manner and in accordance with and subject to the terms and provisions set forth in Article 11 of the Original Indenture), at a Redemption Price
equal to the greater of: 
  

	 	(a)	100% of the principal amount of the Notes to be redeemed; and 

  

	 	(b)	the sum of the present values of the remaining scheduled payments of principal and interest thereon (exclusive of interest accrued to the Redemption Date) discounted to the
Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate, plus 40 basis points in the case of the 2019 Notes, and plus 45 basis points in the case of the 2039 Notes;

 plus in each case accrued interest to the Redemption Date; provided that installments of interest on Notes which are due and payable on any
date falling on or prior to a Redemption Date will be payable to the registered holders of such Notes (or one or more predecessor Notes), registered as such as of the close of business on the relevant Regular Record Dates. 
 The Issuer will provide notice to the Trustee prior to the Redemption Date of the calculation of the Redemption Price. 
  

	3.2	Additional Definitions 

 For the purposes of this
Second Supplemental Indenture, the following expressions shall have the following meanings: 
 “Comparable Treasury Issue”
means the U.S. Treasury security selected by an Independent Investment Banker as having a maturity comparable to the remaining term of the applicable series of Notes to be redeemed that would be utilized, at the time of selection and in accordance
with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of such Notes; 
 “Comparable Treasury Price” means, with respect to any redemption date, (i) the average of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) on
the third business day preceding such redemption date, as set forth in the daily statistical release (or any successor release) published by the Federal Reserve Bank of New York and designated “Composite 3:30 p.m. Quotations for U.S.
Government Securities” or (ii) if such release (or any successor release) is not published or 

 -6- 
  

 
does not contain such prices on such business day, (A) the average of the Reference Treasury Dealer Quotations for such redemption date, after excluding
the highest and lowest such Reference Treasury Dealer Quotations, or (B) if the Issuer is unable to obtain four such Reference Treasury Dealer Quotations, the average of all such Quotations; 
 “Independent Investment Banker” means one of the Reference Dealers selected by the Issuer; 
 “Reference Dealer” means each of Banc of America Securities LLC, BNP Paribas Securities Corp., Deutsche Bank Securities Inc. and HSBC
Securities (USA) Inc. and their respective successors, and two other firms that are primary U.S. government securities dealers in the City of New York (each a “Primary Treasury Dealer”) which the Issuer specifies from time to time;
provided, however, that if any of the foregoing Reference Dealers shall cease to be a Primary Treasury Dealer, the Issuer shall substitute therefor another Primary Treasury Dealer; 
 “Reference Treasury Dealer Quotations” means, with respect to each Reference Dealer and any redemption date, the average, as determined
by the Issuer, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Issuer by such Reference Dealer at 3:30 p.m. (New York City time) on the third
business day preceding such redemption date; and 
 “Treasury Rate” means, with respect to any redemption date, the rate per
year equal to the semi-annual equivalent yield to maturity of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such
redemption date. 
  

	4.	GENERAL 

  

	4.1	Effectiveness 

 This Second Supplemental Indenture
will become effective upon its execution and delivery. 
  

	4.2	Effect of Recitals 

 The recitals contained herein
and in the Securities, except the Trustee’s certificates of authentication, shall be taken as the statements of the Issuer, and neither the Trustee nor any Authenticating Agent assumes any responsibility for their correctness. Neither the
Trustee nor any Authenticating Agent shall be accountable for the use or application by the Issuer of the Securities or the proceeds thereof. The Trustee makes no representations as to the validity or sufficiency of this Second Supplemental
Indenture or of the Securities except that the Trustee represents that it is duly authorized to execute and deliver this Second Supplemental Indenture, authenticate the Securities and perform its obligations under the Original Indenture and
hereunder, and that the statements made by it or to be made by it in a Statement of Eligibility and Qualification on Form T-1 supplied to the Issuer are true and accurate. 

 -7- 
  

	4.3	Ratification of Original Indenture 

 The Original
Indenture as supplemented by this Second Supplemental Indenture is in all respects ratified and confirmed, and this Second Supplemental Indenture shall be deemed part of the Original Indenture in the manner and to the extent herein and therein
provided. 
  

	4.4	Governing Law 

 This Second Supplemental Indenture,
the Original Indenture as supplemented hereby and the Securities shall be governed by and construed in accordance with the laws of the State of New York. 
  

	4.5	Severability 

 In case any provision in this Second
Supplemental Indenture, the Original Indenture as supplemented hereby or in the Securities shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired
thereby. 
  

	4.6	Acceptance of Trust 

 The Trustee hereby accepts the
trusts in this Second Supplemental Indenture declared and provided for and agrees to perform the same upon the terms and conditions herein before set forth in trust for the various Persons who shall from time to time be Note holders subject to all
the terms and conditions herein set forth. 
  

	4.7	Counterparts and Formal Date 

 This Second
Supplemental Indenture may be executed in any number of counterparts, each of which so executed shall be deemed to be an original, but all such counterparts shall together constitute but one and the same instrument and notwithstanding their date of
execution shall be deemed to bear the date first above written. 

 IN WITNESS WHEREOF the parties hereto have executed this Second Supplemental Indenture on the date first
above written. 
  

			
	 NEXEN INC.

		
	Per:	 	 /s/    Kevin J. Reinhart

		 	 Kevin J. Reinhart
 Senior Vice President
and
 Chief Financial Officer

		
	Per:	 	 /s/    J. Michael Backus

		 	 J. Michael Backus
 Treasurer

  

			
	 DEUTSCHE BANK TRUST COMPANY
 AMERICAS, as trustee

	
	 By Deutsche Bank National Trust Company

		
	Per:	 	 /s/    David Contino

		 	 Name: David Contino
 Title: Vice
President

		
	Per:	 	 /s/    Irina Golovashchuk

		 	 Name: Irina Golovashchuk
 Title: Assistant Vice
President

 TABLE OF CONTENTS 
  

					
	 1.
	  	INTERPRETATIONS AND AMENDMENTS	  	2
		  	 1.1    SECOND SUPPLEMENTAL INDENTURE
	  	2
		  	 1.2    DEFINITIONS IN SECOND SUPPLEMENTAL
INDENTURE
	  	2
		  	 1.3    INTERPRETATION NOT AFFECTED BY
HEADINGS
	  	2
			
	 2.
	  	NOTES	  	2
		  	 2.1    FORM AND TERMS OF
NOTES
	  	2
		  	 2.2    ISSUANCE OF NOTES
	  	4
			
	 3.
	  	REDEMPTION OF NOTES	  	5
		  	 3.1    REDEMPTION OF NOTES
	  	5
		  	 3.2    ADDITIONAL DEFINITIONS
	  	5
			
	 4.
	  	GENERAL	  	6
		  	 4.1    EFFECTIVENESS
	  	6
		  	 4.2    EFFECT OF RECITALS
	  	6
		  	 4.3    RATIFICATION OF ORIGINAL INDENTURE
	  	7
		  	 4.4    GOVERNING LAW
	  	7
		  	 4.5    SEVERABILITY
	  	7
		  	 4.6    ACCEPTANCE OF TRUST
	  	7
		  	 4.7    COUNTERPARTS AND FORMAL DATE
	  	7

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00213-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00213-of-00352.parquet"}]]