EX-4.2

THIS SIXTEENTH SUPPLEMENTAL INDENTURE, dated as of April 28, 2015 (the “Sixteenth Supplemental Indenture”), among Carrizo Oil & Gas, Inc., a Texas corporation (the “Company”), the subsidiary guarantors listed on the signature page hereof (each, a “Subsidiary Guarantor” and, collectively, the “Subsidiary Guarantors”) and Wells Fargo Bank, National Association, as trustee (the “Trustee”).

WHEREAS, the Company has heretofore executed and delivered to the Trustee an Indenture, dated as of May 28, 2008 (the “Original Indenture” and, as supplemented by this Sixteenth Supplemental Indenture, the “Indenture”), providing for the issuance from time to time of one or more series of the Company’s Securities;

WHEREAS, Sections 2.01 and 9.01(9) of the Original Indenture provide that the Company and the Trustee may from time to time enter into one or more indentures supplemental thereto to establish the form or terms of Securities of a new series;

WHEREAS, Sections 9.01(6) and 9.01(7) of the Original Indenture permit the execution of supplemental indentures without the consent of any Holders to add to the covenants of the Company for the benefit of, and to add any additional Events of Default with respect to, all or any series of Securities;

WHEREAS, Section 9.01(8) of the Original Indenture permits the execution of supplemental indentures without the consent of any Holders to change or eliminate any of the provisions of the Indenture; provided that such change or elimination does not adversely affect in any material respect any outstanding Security of any series created prior to the execution of such supplemental indenture;

WHEREAS, the Company desires to issue 6.250% Senior Notes due 2023, a new series of Securities the issuance of which was authorized by or pursuant to resolution of the Board of Directors of the Company;

WHEREAS, the Company, pursuant to the foregoing authority, proposes in and by this Sixteenth Supplemental Indenture to supplement and amend the Original Indenture insofar as it will apply only to Notes in certain respects;

WHEREAS, all things necessary have been done to make the Notes, when executed by the Company and authenticated and delivered hereunder and duly issued by the Company, the valid obligations of the Company, and to make this Sixteenth Supplemental Indenture a valid agreement of the Company and of the Subsidiary Guarantors, in accordance with their and its terms; and

WHEREAS, all things necessary have been done to make the Guarantee of each Subsidiary Guarantor, when the Notes are executed by the Company and authenticated and delivered hereunder and duly issued by the Company, the valid obligation of such Subsidiary Guarantor, and to make this Sixteenth Supplemental Indenture a valid agreement of the Subsidiary Guarantors, in accordance with its terms.

In consideration of the premises provided for herein, the Company, the Subsidiary Guarantors and the Trustee mutually covenant and agree for the equal and proportionate benefit of all Holders of the Notes as follows:

There shall be a series of Securities designated “6.250% Senior Notes due 2023” of the Company. References herein to the “Notes” shall mean the Initial Notes and any Additional Notes, taken together as a single series of Securities. The Notes shall be issued subject to the terms of the Appendix hereto, and may have such letters, numbers or other marks of identification and such legends or endorsements placed thereon as may be required to comply with the rules of any securities exchange or as may, consistently herewith, be determined by the officers of the Company executing such Notes, as evidenced by their execution of the Notes.

All of the Notes will initially be issued, as further described in the Appendix hereto, in permanent global form, substantially in the form set forth in Annex A (the “Global Securities”), which is incorporated into and shall be deemed a part of this Sixteenth Supplemental Indenture, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by the Indenture. Each Global Security shall represent such of the Notes as shall be specified therein and shall provide that it shall represent the aggregate amount of Outstanding Notes from time to time endorsed thereon and that the aggregate amount of Outstanding Notes represented thereby may from time to time be reduced to reflect exchanges and redemptions. Any endorsement of a Global Security to reflect the amount, or any increase or decrease in the amount, of Outstanding Notes represented thereby shall be made by the Trustee in accordance with written instructions or such other written form of instructions as is customary for the Depositary, from the Depositary or its nominee on behalf of any Person having the beneficial interest in the Global Security.

The Company initially appoints The Depository Trust Company to act as Depositary with respect to the Global Securities.

The Company initially appoints the Trustee to act as Registrar and Paying Agent with respect to the Notes.

The Notes may be issued in unlimited aggregate principal amount, subject to the requirements of the Indenture. The Trustee shall authenticate and deliver Notes for original issue on the Initial Issuance Date in an aggregate principal amount of up to $650,000,000 upon Company Order without any further action by the Company. Upon Company Request, the Trustee shall authenticate and deliver Additional Notes in accordance with Section 2.18 of the Indenture.

The Notes shall bear interest at the rate set forth under the caption “Interest” in the Notes. Interest on the Notes shall be payable to the persons in whose name the Notes are registered at the close of business on the Regular Record Date (as defined below) for such interest payment. Interest on the Notes shall accrue on the Notes from the date specified in the Notes. The Interest Payment Dates on which interest on the Notes shall be payable are April 15 and October 15, commencing on October 15, 2015. The regular record dates for the interest payable on the Notes on any Interest Payment Date shall be April 1 or October 1, as the case may be, immediately preceding such Interest Payment Date (each, a “Regular Record Date”).

The Notes shall be in fully registered form without coupons in denominations of $2,000 of principal amount and integral multiples of $1,000 in excess of $2,000.

The Place of Payment for the Notes and the place or places where the principal of and interest on the Notes shall be payable, the Notes may be surrendered for registration of transfer, the Notes may be surrendered for exchange, repurchase or redemption and where notices may be given to the Company in respect of the Notes is at the office or agency of the Trustee in Dallas, Texas; provided that payment of interest may be made at the option of the Company by check mailed to the address of the person entitled thereto as such address shall appear in the register of Securities; provided, further if a Holder has given wire transfer instructions to the Company, the Company will pay all principal, interest and premium, if any, on that Holder’s Notes in accordance with such instructions by wire transfer of immediately available funds to the accounts in the United States specified by the Holder of such Notes.

The Company, at its option, may redeem the Notes in accordance with the provisions of and at the Redemption Prices set forth under the caption “Optional Redemption” in the Notes and in accordance with the provisions of the Indenture, including, without limitation, Article III of the Original Indenture.

The date on which the principal of the Notes is payable, unless accelerated pursuant to the Indenture, shall be April 15, 2023.

The Notes shall be repurchased by the Company in accordance with the provisions and at the repurchase prices set forth under the caption “Repurchase by the Company at the Option of Holder” in the Notes and in accordance with the provisions of the Indenture, including, without limitation, Sections 4.12 and 4.16 of the Indenture.

The Notes shall be entitled to the benefits of a Guarantee by each of the Subsidiary Guarantors as provided in Article X of the Original Indenture, as amended hereby.

Without limiting the foregoing provisions of this Article One, the terms of the Notes shall be as set forth in the form of the Note set forth in Annex A hereto and as provided in the Indenture.

The amendments contained herein shall apply to the Notes only and not to any other series of Security issued under the Indenture and any covenants provided herein are expressly being included solely for the benefit of the Notes. These amendments shall be effective for so long as there remain any Notes Outstanding.

Section 1.01 of the Original Indenture is amended by inserting or restating, as the case may be, in their appropriate alphabetical position, the following definitions:

(1) any assets used or useful in the Oil and Gas Business, other than Indebtedness or Capital Stock;

(2) the Capital Stock of a Person that becomes a Restricted Subsidiary as a result of the acquisition of such Capital Stock by the Company or any of its Restricted Subsidiaries; or

(3) Capital Stock constituting a minority interest in any Person that at such time is a Restricted Subsidiary;

provided, however, that any such Restricted Subsidiary described in clause (2) or (3) is primarily engaged in the Oil and Gas Business.

“Additional Notes” means, subject to the Company’s compliance with Section 4.11, 6.250% Senior Notes due 2023 issued from time to time after the Initial Issuance Date under the terms of this Indenture (other than pursuant to Section 2.08, 2.09, 2.12, 3.07, 4.12, 4.16 or 9.05 of this Indenture or Section 2.03 of the Appendix).

“Adjusted Consolidated Net Tangible Assets” of a specified Person means (without duplication), as of the date of determination:

(a) discounted future net revenue from proved crude oil and natural gas reserves of such Person and its Restricted Subsidiaries calculated in accordance with SEC guidelines before any state or federal or other income taxes, as estimated by the Company in a reserve report prepared as of the end of the fiscal year of such Person for which audited financial statements are available, as increased by, as of the date of determination, the estimated discounted future net revenue from:

(i) estimated proved crude oil and natural gas reserves of such Person and its Restricted Subsidiaries attributable to acquisitions consummated since the date of such reserve report, which reserves were not reflected in such reserve report, and

(ii) estimated crude oil and natural gas reserves of such Person and its Restricted Subsidiaries attributable to extensions, discoveries and other additions and upward revisions of estimates of proved crude oil and natural gas reserves (including previously estimated development costs incurred during the period and the accretion of discount since the prior period end) due to exploration, development or exploitation, production or other activities which would, in accordance with standard industry practice, cause such revisions, in the case of clauses (i) and (ii) calculated in accordance with SEC guidelines before any state or federal or other income taxes,

and decreased by, as of the date of determination, the estimated discounted future net revenue attributable to:

(A) estimated proved crude oil and natural gas reserves of such Person and its Restricted Subsidiaries reflected in such reserve report produced or disposed of since the date of such reserve report, and

(B) reductions in the estimated crude oil and natural gas reserves of such Person and its Restricted Subsidiaries reflected in such reserve report since the date of such reserve report due to changes in geological conditions or other factors which would, in accordance with standard industry practice, cause such revisions, in the case of clauses (A) and (B) calculated in accordance with SEC guidelines before any state or federal or other income taxes;

provided, however, that, in the case of each of the determinations made pursuant to clauses (i), (ii), (A) and (B) above, such increases and decreases shall be estimated by the Company’s petroleum engineers or any independent petroleum engineers engaged by the Company for that purpose;

(b) the capitalized costs that are attributable to crude oil and natural gas properties of such Person and its Restricted Subsidiaries to which no proved crude oil and natural gas reserves are attributable, based on such Person’s books and records as of a date no earlier than the date of such Person’s latest available annual or quarterly financial statements;

(c) the Net Working Capital of such Person as of a date no earlier than the date of such Person’s latest available annual or quarterly financial statements; and

(i) the net book value of other tangible assets of such Person and its Restricted Subsidiaries as of a date no earlier than the date of such Person’s latest available annual or quarterly financial statements, and

(ii) the appraised value, as estimated by independent appraisers, of other tangible assets of such Person and its Restricted Subsidiaries as of a date no earlier than the date of such Person’s latest available annual or quarterly financial statements (provided that such Person shall not be required to obtain such an appraisal of such assets if no such appraisal has been performed);

(b) to the extent not otherwise taken into account in determining Adjusted Consolidated Net Tangible Assets, any net natural gas balancing liabilities of such Person and its Restricted Subsidiaries reflected in such Person’s latest audited financial statements;

(c) to the extent included in clause (1)(a) above, the discounted future net revenue, calculated in accordance with SEC guidelines (utilizing the prices utilized in such Person’s year end reserve report) before any state or federal or other income taxes, attributable to reserves subject to participation interests, overriding royalty interests or other interests of third parties, pursuant to participation, partnership, vendor financing or other agreements then in effect, or which otherwise are required to be delivered to third parties;

(d) to the extent included in clause (1)(a) above, the discounted future net revenue calculated in accordance with SEC guidelines (utilizing the prices utilized in such Person’s year end reserve report) before any state or federal or other income taxes, attributable to reserves that are required to be delivered to third parties to fully satisfy the obligations of such Person and its Restricted Subsidiaries with respect to Volumetric Production Payments on the schedules specified with respect thereto; and

(e) the discounted future net revenue, calculated in accordance with SEC guidelines before any state or federal or other income taxes, attributable to reserves subject to Dollar-Denominated Production Payments that, based on the estimates of production and price assumptions included in determining the discounted future net revenue specified in clause (1)(a) above, would be necessary to satisfy fully the obligations of such Person and its Restricted Subsidiaries with respect to Dollar-Denominated Production Payments on the schedules specified with respect thereto.

If the Company changes its method of accounting from the full cost method to the successful efforts method or a similar method of accounting, “Adjusted Consolidated Net Tangible Assets” of the Company will continue to be calculated as if the Company were still using the full cost method of accounting.

“Affiliate” of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For purposes of this definition, “control,” as used with respect to any Person, means the possession, directly or indirectly, of the power to direct or cause the direction of the management or policies of such Person, whether through the ownership of voting securities, by agreement or otherwise. For purposes of this definition, the terms “controlling,” “controlled by” and “under common control with” have correlative meanings.

“Applicable Law,” except as the context may otherwise require, means all applicable laws, rules, regulations, ordinances, judgments, decrees, injunctions, writs and orders of any court or governmental or congressional agency or authority and rules, regulations, orders, licenses and permits of any United States federal, state, municipal, regional, or other governmental body, instrumentality, agency or authority.

(1) the sale, lease, conveyance or other disposition of any assets (including by way of a Production Payment or a Sale Leaseback Transaction or mergers, consolidations or otherwise); provided, however, that the disposition of all or substantially all of the assets of the Company and its Restricted Subsidiaries taken as a whole will not be an “Asset Sale,” but will be governed by the provisions of Section 4.16 or the provisions of Section 5.01 or both, and not by the provisions of Section 4.12; and

(2) the issuance of Equity Interests in any of the Company’s Restricted Subsidiaries or the sale of Equity Interests in any of its Restricted Subsidiaries (other than directors’ qualifying shares or shares required by Applicable Law to be held by a Person other than the Company or a Restricted Subsidiary of the Company).

Notwithstanding the preceding, the following items will not be deemed to be Asset Sales:

(1) any single transaction or series of related transactions that involves properties or assets having a Fair Market Value of less than the greater of (i) $10.0 million and (ii) 1.0% of the Company’s Adjusted Consolidated Net Tangible Assets determined as of the date of such transaction;

(2) a disposition of assets between or among any of the Company and its Restricted Subsidiaries;

(3) an issuance or sale of Equity Interests by a Restricted Subsidiary to the Company or to another Restricted Subsidiary;

(4) any disposition, abandonment, relinquishment or expiration of equipment, inventory, products, accounts receivable or other properties or assets in the ordinary course of business;

(5) the disposition of cash or Cash Equivalents, Hedging Contracts or other financial instruments in the ordinary course of business;

(6) a Restricted Payment that is permitted by Section 4.09 or a Permitted Investment (or a disposition that would constitute a Restricted Payment but for an exclusion from the definition thereof) including the issuance or sale of Equity Interests or the sale, lease or other disposition of products, services, equipment, inventory, accounts receivable or other assets pursuant to any such Restricted Payment or Permitted Investment;

(7) the farm-out, lease or sublease of developed or undeveloped crude oil or natural gas properties owned or held by the Company or any of its Restricted Subsidiaries in the ordinary course of business or in exchange for crude oil and natural gas properties or interests owned or held by another Person;

(8) (i) any trade or exchange by the Company or any of its Restricted Subsidiaries of Hydrocarbon properties or other properties or assets for Hydrocarbon properties or other properties or assets owned or held by one or more other Persons, and (ii) any transfer or sale of assets, or lease, assignment or sublease of any real or personal property, (A) in exchange for services (including in connection with any outsourcing arrangements), (B) in exchange for such transferee, lessee or assignee (or an Affiliate thereof) agreeing to pay all or a portion of the costs and expenses related to the exploration, development, completion or production (and related activities) of properties of the Company or any Restricted Subsidiary, or (C) in exchange for properties or assets satisfying the requirements of clause (i) above, or any combination of clauses (A), (B) or (C) (clauses (A), (B) and (C) being referred to herein as a “carry”); provided that (except in the case of land purchase option arrangements granted by or to the Company or any Restricted Subsidiary of the Company) the Fair Market Value of the properties or assets traded, exchanged, transferred, sold, leased, assigned or subleased by the Company or such Restricted Subsidiary (together with any cash and Cash Equivalents) is reasonably equivalent or of less market value to the Fair Market Value of the properties, assets, services or carry (together with any cash and Cash Equivalents) expected to be received by the Company or such Restricted Subsidiary, as determined in good faith by the Company, and provided further that any cash received must be applied in accordance with the provisions of Section 4.12;

(9) the creation or perfection of a Lien (but not, except to the extent contemplated in clause (10) below, the sale or other disposition of the assets subject to such Lien);

(10) the creation or perfection of a Permitted Lien and the exercise by any Person in whose favor a Permitted Lien is granted of any of its rights in respect of that Permitted Lien;

(11) a surrender or waiver of contract rights or the settlement, release or surrender of contract, tort or other claims of any kind;

(12) the licensing or sublicensing of intellectual property or other general intangibles in the ordinary course of business to the extent that such license does not prohibit the licensor from using the intellectual property and licenses, leases or subleases of other property;

(13) the disposition of oil and natural gas properties in connection with tax credit transactions complying with Section 45K of the Code or any successor or analogous provisions of the Code, provided that the sale or other disposition is for not less than the Fair Market Value of such oil and natural gas properties, as determined in good faith by the Company;

(14) the transfer of property received in settlement of debts owing to such Person as a result of foreclosure, perfection or enforcement of any Lien or debt, which debts were owing to such Person in the ordinary course of its business,

(15) any Production Payments and Reserve Sales, provided that any such Production Payments and Reserve Sales (other than incentive compensation programs on terms that are reasonably customary in the Oil and Gas Business for geologists, geophysicists and other providers of technical services to the Company or a Restricted Subsidiary of the Company), shall have been created, incurred, issued, assumed or guaranteed in connection with the acquisition or financing of, and within 60 days after the acquisition of, the property that is subject thereto;

(16) the sale or other disposition (whether or not in the ordinary course of business) of oil and gas properties, provided at the time of such sale or other disposition such properties do not have associated with them any proved reserves, and provided further that the sale or other disposition is for not less than the Fair Market Value of such oil and gas properties, as determined in good faith by the Company;

(17) any sale or other disposition of Equity Interests in, or other ownership interests in or assets or property, including Indebtedness, or other securities of, an Unrestricted Subsidiary;

(18) any disposition of Equity Interests of a Restricted Subsidiary pursuant to an agreement or other obligation with or to a Person (other than the Company or a Restricted Subsidiary of the Company) from whom such Restricted Subsidiary was acquired or from whom such Restricted Subsidiary acquired its business and assets (having been newly formed in connection with such acquisition), made as part of such acquisition and in each case comprising all or a portion of the consideration in respect of such sale or acquisition; and

(19) the sale and leaseback of any asset within 180 days of the acquisition thereof.

“Attributable Debt” in respect of a Sale Leaseback Transaction means, at the time of determination, the present value of the obligation of the lessee for net rental payments during the remaining term of the lease included in such Sale Leaseback Transaction including any period for which such lease has been extended or may, at the option of the lessor, be extended. Such present value shall be calculated using a discount rate equal to the rate of interest implicit in such transaction, determined in accordance with GAAP. As used in the preceding sentence, the “net rental payments” under any lease for any period shall mean the sum of rental and other payments required to be paid with respect to such period by the lessee thereunder, excluding any amounts required to be paid by such lessee on account of maintenance and repairs, insurance, taxes, assessments, water rates or similar charges. In the case of any lease that is terminable by the lessee upon payment of penalty, such net rental payment shall also include the amount of such penalty, but no rent shall be considered as required to be paid under such lease subsequent to the first date upon which it may be so terminated.

“Avista” means Avista Capital Holdings, LP, a Delaware limited partnership, and its successors and permitted assigns.

“Avista Joint Venture” means that certain joint venture between Carrizo (Marcellus) LLC (or other wholly owned Subsidiaries of the Company) Avista Capital Partners II, L.P. and ACP II Marcellus LLC pursuant to that certain Participation Agreement dated as of November 3, 2008 and such other documents delivered in connection therewith, in each case as amended or supplemented as of the Initial Issuance Date, as the same may be amended, modified or supplemented from time to time (provided that such further amendment, modification or supplement does not materially and adversely affect the rights of any Holder of Notes).

“Beneficial Owner” has the meaning assigned to such term in Rule 13d-3 and Rule 13d-5 under the Exchange Act, except that in calculating the beneficial ownership of any particular “person” (as that term is used in Section 13(d)(3) of the Exchange Act), such “person” will be deemed to have beneficial ownership of all securities that such “person” has the right to acquire by conversion or exercise of other securities, whether such right is currently exercisable or is exercisable only upon the occurrence of a subsequent condition. The terms “Beneficially Owns” and “Beneficially Owned” have correlative meanings.

(1) with respect to the Company, the board of directors of the Company or any authorized committee thereof; and

(2) with respect to any other Person, the board or committee of such Person serving a similar function.

“Board Resolution” means a copy of a resolution certified by the Secretary or an Assistant Secretary of the applicable Person to have been duly adopted by the Board of Directors of such Person and to be in full force and effect on the date of such certification, and delivered to the Trustee.

“Capital Lease Obligation” means, at the time any determination is to be made, the amount of the liability in respect of a capital lease that would at that time be required to be capitalized on a balance sheet in accordance with GAAP, and the Stated Maturity thereof shall be the date of the last payment of rent or any other amount due under such lease prior to the first date upon which such lease may be prepaid by the lessee without payment of a penalty.

(2) in the case of an association or business entity, any and all shares, interests, participations, rights or other equivalents (however designated) of corporate stock;

(3) in the case of a partnership or limited liability company, partnership interests (whether general or limited) or membership interests; and

(4) any other interest or participation that confers on a Person the right to receive a share of the profits and losses of, or distributions of assets of, the issuing Person,

but excluding from all of the foregoing any debt securities convertible into Capital Stock, regardless of whether such debt securities include any right of participation with Capital Stock.

(2) securities issued or directly and fully guaranteed or insured by the United States government or any agency or instrumentality of the United States government (provided that the full faith and credit of the United States is pledged in support of those securities) having maturities of not more than one year from the date of acquisition;

(3) marketable general obligations issued by any state of the United States of America or any political subdivision of any such state or any public instrumentality thereof maturing within one year from the date of acquisition thereof and, at the time of acquisition thereof, having a credit rating of “A” or better from either S&P or Moody’s;

(4) certificates of deposit, demand deposits and eurodollar time deposits with maturities of one year or less from the date of acquisition, bankers’ acceptances with maturities not exceeding one year and overnight bank deposits, in each case, with any domestic commercial bank having capital and surplus in excess of $500.0 million;

(5) repurchase obligations with a term of not more than seven days for underlying securities of the types described in clauses (2), (3) and (4) above entered into with any financial institution meeting the qualifications specified in clause (4) above;

(6) commercial paper having one of the two highest ratings obtainable from Moody’s or S&P and, in each case, maturing within one year after the date of acquisition; and

(7) money market funds at least 95% of the assets of which constitute Cash Equivalents of the kinds described in clauses (1) through (6) of this definition.

(1) the direct or indirect sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or a series of related transactions, of all or substantially all of the assets (including Capital Stock of the Restricted Subsidiaries) of the Company and its Restricted Subsidiaries taken as a whole, or a Successor Parent of the Company and its Restricted Subsidiaries taken as a whole, to any “person” (as that term is used in Section 13(d)(3) of the Exchange Act) other than a Permitted Holder;

(2) the adoption by the shareholders of the Company of a plan relating to the liquidation or dissolution of the Company;

(3) the consummation of any transaction (including, without limitation, any merger or consolidation) the result of which is that any “person” (as that term is used in Section 13(d)(3) of the Exchange Act), other than Permitted Holders, becomes the Beneficial Owner, directly or indirectly, of more than 50% of the Voting Stock of the Company, or any Successor Parent of the Company, measured by voting power rather than number of shares, units or the like; provided that no Change of Control shall be deemed to occur by reason of the Company becoming a Subsidiary of any Successor Parent; or

(4) the first day on which a majority of the members of the Board of Directors of the Company or any Successor Parent of the Company are not Continuing Directors.

“Code” means the Internal Revenue Code of 1986, as amended from time to time, and any successor statute.

“Consolidated Cash Flow” means, with respect to any specified Person for any period, the Consolidated Net Income of such Person for such period plus, without duplication:

(1) an amount equal to any net loss realized by such Person or any of its Restricted Subsidiaries in connection with an Asset Sale, to the extent such losses were deducted in computing such Consolidated Net Income; plus

(2) provision for taxes based on income or profits of such Person and its Restricted Subsidiaries for such period, to the extent that such provision for taxes was deducted in computing such Consolidated Net Income; plus

(3) the Fixed Charges of such Person and its Restricted Subsidiaries for such period, to the extent that such Fixed Charges were deducted in computing such Consolidated Net Income; plus

(4) depreciation, depletion, amortization (including amortization of intangibles but excluding amortization of prepaid cash expenses that were paid in a prior period), impairment and other non-cash expenses (excluding any such non-cash expense to the extent that it represents an accrual of or reserve for cash expenses in any future period or amortization of a prepaid cash expense that was paid in a prior period) of such Person and its Restricted Subsidiaries for such period to the extent that such depreciation, depletion, amortization, impairment and other non-cash expenses were deducted in computing such Consolidated Net Income; plus

(5) unrealized non-cash losses resulting from foreign currency balance sheet adjustments required by GAAP to the extent such losses were deducted in computing such Consolidated Net Income; plus

(6) all extraordinary, unusual or non-recurring items of gain or loss, or revenue or expense; minus

(7) non-cash items increasing such Consolidated Net Income for such period, other than items that were accrued in the ordinary course of business; and minus

(8) to the extent increasing such Consolidated Net Income for such period, the sum of (a) the amount of deferred revenues that are amortized during such period and are attributable to reserves that are subject to Volumetric Production Payments and (b) amounts recorded in accordance with GAAP as repayments of principal and interest pursuant to Dollar-Denominated Production Payments;

“Consolidated Net Income” means, with respect to any specified Person for any period, the aggregate of the Net Income of such Person and its Restricted Subsidiaries for such period, on a consolidated basis, determined in accordance with GAAP, provided that:

(1) the Net Income (but not loss) of any Person that is not a Restricted Subsidiary or that is accounted for by the equity method of accounting will be included, but only to the extent of the amount of dividends or distributions paid in cash to the specified Person or a Restricted Subsidiary of the Person;

(2) the Net Income of any Restricted Subsidiary of the Company will be excluded to the extent that the declaration or payment of dividends or similar distributions by that Restricted Subsidiary of that Net Income is not at the date of determination permitted without any prior governmental approval (that has not been obtained) or, directly or indirectly, by operation of the terms of its charter or any agreement, instrument, judgment, decree, order, statute, rule or governmental regulation applicable to that Restricted Subsidiary or its stockholders, partners or members;

(3) the cumulative effect of a change in accounting principles will be excluded;

(4) any gain (loss) realized upon the sale or other disposition of any property, plant or equipment of such Person or its consolidated Restricted Subsidiaries (including pursuant to any sale or leaseback transaction) which is not sold or otherwise disposed of in the ordinary course of business and any gain (loss) realized upon the sale or other disposition of any Capital Stock of any Person will be excluded;

(5) any asset impairment writedowns on oil and gas properties under GAAP or SEC guidelines will be excluded;

(6) unrealized losses and gains under Hedging Contracts included in the determination of Consolidated Net Income, including, without limitation, those resulting from the application of FASB ASC Topic 815, “Derivatives and Hedging,” will be excluded;

(7) to the extent deducted in the calculation of Net Income, any non-cash or nonrecurring charges relating to any premium or penalty paid, write off of deferred financing costs or other financial recapitalization charges in connection with redeeming or retiring any Indebtedness prior to its Stated Maturity will be excluded;

(8) items classified as extraordinary or nonrecurring gains and losses (less all fees and expenses related thereto) and the related tax effects, in each case according to GAAP, will be excluded; and

(9) income resulting from transfers of assets (other than cash) between such Person or any of its Restricted Subsidiaries, on the one hand, and an Unrestricted Subsidiary of such Person, on the other hand, will be excluded.

“Consolidated Net Worth” means, with respect to any specified Person as of any date, the sum of:

(1) the consolidated equity of the common shareholders of, or the consolidated capital of the unitholders of, such Person and its consolidated Subsidiaries as of such date; plus

(2) the respective amounts reported on such Person’s balance sheet as of such date with respect to any series of preferred stock (other than Disqualified Stock) that by its terms is not entitled to the payment of dividends unless such dividends may be declared and paid only out of net earnings in respect of the year of such declaration and payment, but only to the extent of any cash received by such Person upon issuance of such preferred stock.

“Continuing Directors” means, as of any date of determination, any member of the Board of Directors of the Company who:

(2) was nominated for election or elected or appointed to such Board of Directors with the approval of a majority of the Continuing Directors who were members of such Board at the time of such nomination, election or appointment.

“Credit Agreement” means that certain Credit Agreement, dated as of January 27, 2011, among the Company, Wells Fargo Bank, National Association, as Administrative Agent, and the lenders party thereto, including any related notes, guarantees, collateral documents, instruments and agreements executed in connection therewith, in each case as amended, restated, modified, renewed, refunded, replaced or refinanced from time to time.

“Credit Facilities” means one or more debt facilities (including, without limitation, the Credit Agreement), commercial paper facilities or Debt Issuances, in each case with banks or other institutional lenders or institutional investors providing for revolving credit loans, term loans, receivables financing (including through the sale of receivables to such lenders or to special purpose entities formed to borrow from such lenders against such receivables), letters of credit or other borrowings or Debt Issuances, in each case, as amended, restated, modified, renewed, refunded, replaced or refinanced (including refinancing with any capital markets transaction) in whole or in part from time to time.

“Custodian” means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

“Customary Recourse Exceptions” means, with respect to any Non-Recourse Debt of an Unrestricted Subsidiary, exclusions from the exculpation provisions with respect to such Non-Recourse Debt for the voluntary bankruptcy of such Unrestricted Subsidiary, fraud, misapplication of cash, environmental claims, waste, willful destruction, and other circumstances customarily excluded by lenders from exculpation provisions or included in separate indemnification agreements in non-recourse financings.

“Debt Issuance” means, with respect to the Company or any of its Restricted Subsidiaries, one or more issuances after the Initial Issuance Date of Indebtedness evidenced by notes, debentures, bonds or other similar securities or instruments.

“De Minimis Guaranteed Amount” means a principal amount of Indebtedness that does not exceed $5.0 million.

“Disqualified Stock” means any Capital Stock that, by its terms (or by the terms of any security into which it is convertible, or for which it is exchangeable, in each case at the option of the holder of the Capital Stock), or upon the happening of any event, matures or is mandatorily redeemable, pursuant to a sinking fund obligation or otherwise, or redeemable at the option of the holder of the Capital Stock, in whole or in part, on or prior to the date that is 91 days after the earlier of the final stated maturity date of the Notes or the date the Notes are no longer outstanding; provided that only the portion of Capital Stock which so matures or is mandatorily redeemable, is so convertible or exchangeable or is so redeemable at the option of the holder thereof prior to such date shall be deemed to be Disqualified Stock; provided, further, that if such Capital Stock is issued to any employee or to any plan for the benefit of employees of the Company or its Subsidiaries or by any such plan to such employees, such Capital Stock shall not constitute Disqualified Stock solely because it may be required to be repurchased by the Company in order to satisfy applicable statutory or regulatory obligations or as a result of such employee’s termination, death or disability; provided, further, that any class of Capital Stock of such Person that by its terms authorizes such Person to satisfy its obligations thereunder by delivery of Capital Stock that is not Disqualified Stock shall not be deemed to be Disqualified Stock. Notwithstanding the preceding sentence, any Capital Stock that would constitute Disqualified Stock solely because the holders of the Capital Stock have the right to require the Company to repurchase or redeem such Capital Stock upon the occurrence of a change of control or an asset sale will not constitute Disqualified Stock if (x) the terms of such Capital Stock provide that the Company may not repurchase or redeem any such Capital Stock pursuant to such provisions unless such repurchase or redemption complies with Section 4.09 or (y) the terms of such Capital Stock provide that the Company may not repurchase or redeem any such Capital Stock pursuant to such provisions prior to the Company’s purchase of the Notes as is required to be purchased pursuant to the terms of this Indenture. The amount (or principal amount) of Disqualified Stock deemed to be outstanding at any time for purposes of this Indenture will be the maximum amount that the Company and its Restricted Subsidiaries may become obligated to pay upon the maturity of, or pursuant to any mandatory redemption provisions of, such Disqualified Stock, exclusive of accrued dividends.

“Dollar-Denominated Production Payments” means production payment obligations recorded as liabilities in accordance with GAAP, together with all undertakings and obligations in connection therewith.

“Domestic Subsidiary” means any Restricted Subsidiary of the Company that was formed under the laws of the United States or any state of the United States or the District of Columbia.

“Equity Interests” means Capital Stock and all warrants, options or other rights to acquire Capital Stock (but excluding any debt security that is convertible into, or exchangeable for, Capital Stock).

“Equity Offering” means any public or private sale of Capital Stock (other than Disqualified Stock) made for cash on a primary basis by the Company after the Initial Issuance Date.

“Existing Indebtedness” means the aggregate principal amount of Indebtedness of the Company and its Restricted Subsidiaries (other than Indebtedness under the Credit Agreement and intercompany Indebtedness) in existence on the Initial Issuance Date, until such amounts are repaid.

“Fair Market Value” means, with respect to any asset, the sale value that would be obtained in an arm’s-length free market transaction between an informed and willing seller under no compulsion to sell and an informed and willing buyer under no compulsion to buy, determined on the date of contractually agreeing to such sale, or in circumstances in which the Company or a Restricted Subsidiary of the Company grants a third party the right to purchase an asset, the date of such grant.

“Fixed Charge Coverage Ratio” means with respect to any specified Person for any four-quarter reference period, the ratio of the Consolidated Cash Flow of such Person for such period to the Fixed Charges of such Person for such period. In the event that the specified Person or any of its Restricted Subsidiaries incurs, assumes, guarantees, repays, repurchases, redeems, defeases or otherwise discharges any Indebtedness (other than ordinary working capital borrowings) or issues, repurchases or redeems preferred stock subsequent to the commencement of the applicable four-quarter reference period and on or prior to the date on which the event for which the calculation of the Fixed Charge Coverage Ratio is made (the “Calculation Date”), then the Fixed Charge Coverage Ratio will be

calculated giving pro forma effect to such incurrence, assumption, guarantee, repayment, repurchase, redemption, defeasance or other discharge of Indebtedness, or such issuance, repurchase or redemption of preferred stock, and the use of the proceeds therefrom, as if the same had occurred at the beginning of the applicable four-quarter reference period.

(1) acquisitions that have been made by the specified Person or any of its Restricted Subsidiaries, including through mergers, consolidations or otherwise (including acquisitions of assets used or useful in the Oil and Gas Business), or any Person or any of its Restricted Subsidiaries acquired by the specified Person or any of its Restricted Subsidiaries, and including in each case any related financing transactions and increases in ownership of Restricted Subsidiaries, during the applicable four-quarter reference period or subsequent to such reference period and on or prior to the Calculation Date, will be given pro forma effect as if they had occurred on the first day of the four-quarter reference period, and the Consolidated Cash Flow for such reference period will be calculated giving pro forma effect to any expense and cost reductions or synergies that have occurred or are reasonably expected to occur, in the reasonable judgment of the chief financial or accounting officer of the Company (provided those cost savings or operating improvements could then be reflected in pro forma financial statements in accordance with Regulation S-X promulgated under the Securities Act or any other regulation or policy of the SEC related thereto);

(2) the Consolidated Cash Flow attributable to discontinued operations, as determined in accordance with GAAP, and operations or businesses (and ownership interests therein) disposed of prior to the Calculation Date, will be excluded;

(3) the Fixed Charges attributable to discontinued operations, as determined in accordance with GAAP, and operations or businesses (and ownership interests therein) disposed of prior to the Calculation Date, will be excluded, but only to the extent that the obligations giving rise to such Fixed Charges will not be obligations of the specified Person or any of its Restricted Subsidiaries following the Calculation Date;

(4) any Person that is a Restricted Subsidiary of the specified Person on the Calculation Date will be deemed to have been a Restricted Subsidiary of the specified Person at all times during such four-quarter period;

(5) any Person that is not a Restricted Subsidiary of the specified Person on the Calculation Date will be deemed not to have been a Restricted Subsidiary of the specified Person at any time during such four-quarter period; and

(6) if any Indebtedness bears a floating rate of interest, the interest expense on such Indebtedness will be calculated as if the rate in effect on the Calculation Date had been the applicable rate for the entire period (taking into account any obligations arising under any Hedging Contract applicable to such Indebtedness if such Hedging Contract has a remaining term as at the Calculation Date in excess of 12 months).

“Fixed Charges” means, with respect to any specified Person for any period, the sum, without duplication, of:

(1) the consolidated interest expense of such Person and its Restricted Subsidiaries for such period, whether paid or accrued (excluding any interest attributable to Dollar-Denominated Production Payments but including, without limitation, amortization of debt issuance costs and original issue discount, non-cash interest payments, the interest component of any deferred payment obligations, the interest component of all payments associated with Capital Lease Obligations, imputed interest with respect to Attributable Debt, commissions, discounts and other fees and charges incurred in respect of letter of credit or bankers’ acceptance financings), and net of the effect of all payments made or received pursuant to interest rate Hedging Contracts; plus

(2) the consolidated interest expense of such Person and its Restricted Subsidiaries that was capitalized during such period; plus

(3) any interest expense on Indebtedness of another Person that is guaranteed by such Person or one of its Restricted Subsidiaries or secured by a Lien on assets of such Person or one of its Restricted Subsidiaries, whether or not such guarantee or Lien is called upon (other than a Lien of the type described in clause (9) of the definition of “Permitted Liens”); plus

(4) all dividends on any Disqualified Stock or series of preferred securities of such Person or any of its Restricted Subsidiaries, whether paid or accrued and whether or not in cash, other than dividends on Equity Interests payable solely in Equity Interests of the Company (other than Disqualified Stock) or to the Company or a Restricted Subsidiary of the Company,

“GAAP” means generally accepted accounting principles in the United States, as in effect on November 2, 2010.

“guarantee” means a guarantee other than by endorsement of negotiable instruments for collection in the ordinary course of business, direct or indirect, in any manner including, without limitation, by way of a pledge of assets or through letters of credit or reimbursement agreements in respect thereof, of all or any part of any Indebtedness or entered into for purposes of assuring in any other manner the obligee of such Indebtedness of the payment thereof or to protect such obligee against loss in respect thereof (in whole or in part). When used as a verb, “guarantee” has a correlative meaning.

(1) interest rate swap agreements, interest rate cap agreements and interest rate collar agreements entered into with one of more financial institutions and designed to protect the Person or any of its Restricted Subsidiaries entering into the agreement against fluctuations in interest rates, or to otherwise reduce the cost of borrowing of such Person or any of such Restricted Subsidiaries, with respect to Indebtedness incurred;

(2) foreign exchange contracts and currency protection agreements entered into with one of more financial institutions and designed to protect the Person or any of its Restricted Subsidiaries entering into the agreement against fluctuations in currency exchange rates;

(3) any commodity futures contract, commodity swap, commodity option, commodity forward sale or other similar agreement or arrangement designed to protect against fluctuations in the price of Hydrocarbons used, produced, processed or sold by that Person or any of its Restricted Subsidiaries at the time; and

(4) other agreements or arrangements designed to protect such Person or any of its Restricted Subsidiaries against fluctuations in interest rates, commodity prices or currency exchange rates,

and in each case are entered into only in the normal course of business and not for speculative purposes.

“Holder” or “Noteholder” means a Person in whose name a Note is registered.

“Hydrocarbons” means crude oil, natural gas, casinghead gas, drip gasoline, natural gasoline, condensate, distillate, liquid hydrocarbons, gaseous hydrocarbons and all constituents, elements or compounds thereof and products refined or processed therefrom.

(1) any indebtedness of such Person, whether or not contingent in respect of borrowed money;

(2) all obligations evidenced by bonds, notes, debentures or similar instruments or letters of credit (or reimbursement agreements in respect thereof) (other than performance, surety and appeal bonds arising in the ordinary course of business);

(4) all Capital Lease Obligations or Attributable Debt in respect of Sale Leaseback Transactions;

(5) all obligations representing the balance deferred and unpaid of the purchase price of any property (other than (i) property purchased, and expense accruals and deferred compensation items arising in the ordinary course of business, (ii) obligations payable solely in Capital Stock that is not Disqualified Stock and (iii) purchase price holdbacks in respect of a portion of the purchase price of an asset to satisfy warranty or other unperformed obligations of the respective seller);

(7) with respect to Production Payments, any warranties or guarantees of production or payment by such Person with respect to such Production Payment, but excluding other contractual obligations of such Person with respect to such Production Payment;

if and to the extent any of the preceding items (other than letters of credit and obligations under Hedging Contracts) would appear as a liability upon a balance sheet of the specified Person prepared in accordance with GAAP. In addition, the term “Indebtedness” includes all Indebtedness of other Persons secured by a Lien on any asset of the specified Person, whether or not such Indebtedness is assumed by the specified Person (provided that the amount of such Indebtedness will be the lesser of (a) the Fair Market Value of such asset at such date of determination and (b) the amount of such Indebtedness of such other Person), and, to the extent not otherwise included, the guarantee by the specified Person of any Indebtedness of any other Person (including, with respect to any Production Payment, any warranties or guarantees of production or payment by such Person with respect to such Production Payment, but excluding other contractual obligations of such Person with respect to such Production Payment).

Notwithstanding the foregoing, the following shall not constitute or be deemed “Indebtedness”:

(i) any indebtedness which has been defeased in accordance with GAAP or defeased pursuant to the deposit of cash or Cash Equivalents (in an amount sufficient to satisfy all such indebtedness obligations at maturity or redemption, as applicable, and all payments of interest and premium, if any) in a trust or account created or pledged for the sole benefit of the holders of such indebtedness, and subject to no other Liens, and the other applicable terms of the instrument governing such indebtedness;

(ii) any obligation of a Person in respect of the balance deferred and unpaid of the purchase price of any property, a farm-in agreement, joint venture, participation or similar arrangement whereby such Person agrees to pay all or a share of the exploration, development, completion or production or other expenses of an exploratory or development well or program (which agreement may be subject to a maximum payment obligation, after which expenses are shared in accordance with the working or participation interest therein or in accordance with the agreement of the parties) or perform the drilling, completion or other operation on such well or program, or transfer of overriding royalty interests or other interests in Hydrocarbon properties in exchange for an ownership interest in an oil or gas property;

(iii) any obligations arising from agreements of a Person providing for indemnification, guarantees, adjustment of purchase price, holdbacks, contingent payment obligations based on a final financial statement or performance of acquired or disposed of assets or similar obligations (other than guarantees of Indebtedness), in each case, incurred or assumed by such Person in connection with the acquisition or disposition of assets (including through mergers, consolidations or otherwise);

(iv) subject to clause (7) above, any Dollar-Denominated Production Payments or Volumetric Production Payments;

(v) any Lien of the type described in clause (9) of the definition of “Permitted Liens;”

(vi) obligations with respect to letters of credit in support of trade obligations or incurred in connection with public liability insurance, workers’ compensation, unemployment insurance, old-age pensions and other social security benefits other than in respect of employee benefit plans subject to the Employee Retirement Income Security Act of 1974, as amended;

(viii) the repayment or reimbursement obligations of the Company or any Restricted Subsidiary with respect to Customary Recourse Exceptions shall not be considered Indebtedness unless and until an event or circumstance occurs that triggers the Company’s or such Restricted Subsidiary’s direct payment liability or reimbursement obligation (as opposed to contingent or performance obligations) to the lender or other party to whom such obligation is actually owed, in which case the amount of such direct payment liability to such lender or other party shall, to the extent otherwise applicable, constitute Indebtedness; and

(ix) in connection with the purchase by the Company or any Restricted Subsidiary of any property, the term “Indebtedness” will exclude post-closing payment adjustments to which the seller may become entitled to the extent such payment is determined by a closing purchase price adjustment or such payment depends on the performance of such property after the closing; provided, however, that, at the time of closing, the amount of any such payment is not determinable and, to the extent such payment at a later date becomes finally fixed and determined by the parties to the purchase, the amount is paid within 30 days after such date.

The amount (or principal amount) of any Indebtedness outstanding as of any date will be:

(1) the accreted value of the Indebtedness, in the case of any Indebtedness issued with original issue discount;

(2) in the case of obligations under any Hedging Contracts, the termination value of the agreement or arrangement giving rise to such obligations that would be payable by such Person at such date; and

(3) the principal amount of the Indebtedness, together with any interest on the Indebtedness that is more than 30 days past due, in the case of any other Indebtedness.

The amount of Indebtedness of any Person at any date will be the outstanding balance at such date of all unconditional obligations as described above and the maximum liability, upon the occurrence of the contingency giving rise to the obligation, of any contingent obligations at such date.

“Initial Notes” means the Notes issued under this Indenture on the Initial Issuance Date, together with all other Notes issued upon registration of transfer of, or in exchange for, such Notes.

“Investment Grade Rating” means a rating equal to or higher than Baa3 (or the equivalent) by Moody’s and BBB- (or the equivalent) by S&P (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments), in each case, with a stable or better outlook.

“Investments” means, with respect to any Person, all direct or indirect investments by such Person in other Persons (including Affiliates) in the forms of loans, advances or extensions of credit (including guarantees or similar arrangements, but excluding (1) commission, travel and similar advances to officers, directors, employees and consultants made in the ordinary course of business and (2) advances to Persons in the ordinary course of business that are recorded as accounts receivable on the balance sheet of the lender), or capital contributions or purchases or other acquisitions for consideration of Indebtedness, Equity Interests or other securities (excluding any interest in a crude oil or natural gas leasehold to the extent constituting a security under applicable law), together with all items that are or would be classified as investments on a balance sheet of such Person prepared in accordance with GAAP. If the Company or any Restricted Subsidiary of the Company sells or otherwise disposes of any Equity Interests of any direct or indirect Restricted Subsidiary of the Company such that, after giving effect to any such sale or disposition, such Person is no longer a Restricted Subsidiary of the Company, the Company will be deemed to have made an Investment on the date of any such sale or disposition in an amount equal to the Fair Market Value of the Equity Interests of such Restricted Subsidiary not sold or disposed of in an amount determined as provided in the final paragraph of Section 4.09. The acquisition by the Company or any Subsidiary of the Company of a Person that holds an Investment in a third Person will be deemed to be an Investment made by the Company or such Subsidiary in such third Person in an amount equal to the Fair Market Value of the Investment held by the acquired Person in such third Person on the date of any such acquisition in an amount determined as provided in the final paragraph of Section 4.09. Except as otherwise provided in this Indenture, the amount of an Investment will be determined at the time the Investment is made and without giving effect to subsequent changes in value or write-ups, write-downs or write-offs with respect to such Investment.

“Joint Venture” means any Person that is not a direct or indirect Subsidiary of the Company in which the Company or any of its Restricted Subsidiaries makes any Investment.

“Lien” means, with respect to any asset, any mortgage, lien, pledge, charge, security interest or encumbrance of any kind in respect of such asset, whether or not filed, recorded or otherwise perfected under Applicable Law, including any conditional sale or other title retention agreement, or any lease in the nature thereof, other than a precautionary financing statement respecting a lease not intended as a security agreement.

“Make Whole Premium” means, with respect to a Note at any time, the excess, if any, of (a) the present value at such time of (i) the Redemption Price of such Note at April 15, 2018 pursuant to Section 3.12(a) plus (ii) any required interest payments due on such Note through April 15, 2018 (except for currently accrued and unpaid interest), computed using a discount rate equal to the Treasury Rate at such time plus 50 basis points, discounted to the Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months), over (b) the principal amount of such Note.

“Minority Interest” means the percentage interest represented by any shares of stock of any class of Capital Stock of a Restricted Subsidiary of the Company that are not owned by the Company or a Restricted Subsidiary of the Company.

“Moody’s” means Moody’s Investors Service, Inc. or any successor to the rating agency business thereof.

“Net Income” means, with respect to any specified Person, the net income (loss) of such Person, determined in accordance with GAAP and before any reduction in respect of preferred stock dividends, excluding, however:

(1) any gain (but not loss), together with any related provision for taxes on such gain (but not loss), realized in connection with: (a) any Asset Sale; or (b) the disposition of any securities by such Person or any of its Restricted Subsidiaries or the extinguishment of any Indebtedness of such Person or any of its Restricted Subsidiaries; and

(2) any extraordinary gain (but not loss), together with any related provision for taxes on such extraordinary gain (but not loss).

“Net Proceeds” means the aggregate cash proceeds received by the Company or any of its Restricted Subsidiaries in respect of any Asset Sale (including any cash payments received by way of deferred payment of principal pursuant to a note or installment receivable or otherwise and net proceeds from the sale or other disposition of any securities received as consideration, but only as and when received, but excluding any other consideration received in the form of assumption by the acquiring Person of Indebtedness or other obligations relating to the properties or assets that are the subject of such Asset Sale or received in any other non-cash form), net of:

(1) the direct costs relating to such Asset Sale, including, without limitation, legal, accounting and investment banking fees, title and recording tax expenses and sales commissions, and any relocation and severance expenses and charges of personnel incurred as a result of the Asset Sale,

(2) taxes paid or payable or required to be accrued as a liability under GAAP as a result of the Asset Sale, in each case, after taking into account any available tax credits or deductions and any tax sharing arrangements,

(3) amounts required to be applied to the repayment of Indebtedness secured by a Lien on the assets that were the subject of such Asset Sale, or which must by its terms, or in order to obtain a necessary consent to such Asset Sale or by Applicable Law, be repaid out of the proceeds from such Asset Sale,

(4) all distributions and other payments required to be made to minority interest holders in Restricted Subsidiaries or Joint Ventures as a result of such Asset Sale, and

(5) any amounts to be set aside in any reserve established in accordance with GAAP or any amount placed in escrow, in either case for adjustment in respect of the sale price of such assets or for liabilities associated with such Asset Sale and retained by the Company or any of its Restricted Subsidiaries until such time as such reserve is reversed or such escrow arrangement is terminated, in which case Net Proceeds shall include only the amount of the reserve so reversed or the amount returned to the Company or its Restricted Subsidiaries from such escrow arrangement, as the case may be.

“Net Working Capital” means (a) all current assets of the Company and its Restricted Subsidiaries except current assets from commodity price risk management activities arising in the ordinary course of business, less (b) all current liabilities of the Company and its Restricted Subsidiaries, except current liabilities included in Indebtedness and any current liabilities from commodity price risk management activities arising in the ordinary course of business, in each case as set forth in the consolidated financial statements of the Company prepared in accordance with GAAP (excluding any adjustments made pursuant to FASB ASC Topic 815, “Derivatives and Hedging”).

(1) as to which neither the Company nor any of its Restricted Subsidiaries (a) provides credit support of any kind (including any undertaking, agreement or instrument that would constitute Indebtedness), (b) is directly or indirectly liable as a guarantor or otherwise, or (c) is the lender, except (i) pursuant to a Lien of the type permitted by item (9) in the definition of “Permitted Lien,” (ii) as described in clause (13) of Section 4.09, (iii) Customary Recourse Exceptions and (iv) a guarantee by the Company or any Restricted Subsidiary of Indebtedness of any Affiliate of the Company, in which case (unless the incurrence of such guarantee resulted in a Restricted Payment at the time of incurrence) the Company shall be deemed to have made a Restricted Payment at the time such Affiliate is designated an Unrestricted Subsidiary, or at the time of such guarantee, if later, equal to the principal amount of any such Indebtedness to the extent guaranteed; and

(2) no default with respect to which (including any rights that the holders of the Indebtedness may have to take enforcement action against an Unrestricted Subsidiary) would permit upon notice, lapse of time or both any holder of any other Indebtedness (other than the Notes and any guarantee permitted by clause (ii) or (iv) in the preceding paragraph) of the Company or any of its Restricted Subsidiaries to declare a default on such other Indebtedness or cause the payment of the Indebtedness to be accelerated or payable prior to its Stated Maturity.

For purposes of determining compliance with Section 4.11, in the event that any Non-Recourse Debt of any of the Company’s Unrestricted Subsidiaries ceases to be Non-Recourse Debt of such Unrestricted Subsidiary, such event will be deemed to constitute an incurrence of Indebtedness by a Restricted Subsidiary of the Company.

“Notes” has the meaning set forth in Section 101 of this Sixteenth Supplemental Indenture.

“Obligations” means any principal, premium, if any, interest (including interest accruing on or after the filing of any petition in bankruptcy or for reorganization, whether or not a claim for post-filing interest is allowed in such proceeding), penalties, fees, charges, expenses, indemnifications, reimbursement obligations, damages, guarantees, and other liabilities or amounts payable under the documentation governing any Indebtedness or in respect thereto.

(1) the acquisition, exploration, development, production, operation and disposition of interests in oil, gas, liquid natural gas, carbon dioxide and other Hydrocarbon properties;

(2) the gathering, marketing, treating, processing, refining, storage, distribution, selling and transporting of any production from such interests or properties;

(3) any business relating to exploration for or development, production, treatment, processing, refining, storage, transportation or marketing of, oil, gas and other minerals and products produced in association therewith;

(4) any activity that is ancillary, complementary or incidental to or necessary or appropriate for the activities described in clauses (1) through (3) of this definition.

“Outstanding,” when used with respect to the Notes, means, as of the date of determination, all Notes theretofore authenticated and delivered under this Indenture, except:

(i) Notes theretofore cancelled by the Trustee or delivered to the Trustee for cancellation;

(ii) Notes for whose payment, repurchase, redemption or defeasance money in the necessary amount has been theretofore deposited with the Trustee or any Paying Agent (other than the Company) in trust or set aside and segregated in trust by the Company (if the Company shall act as its own Paying Agent) for the Holders of such Notes; provided that, if such Notes are to be redeemed, notice of such redemption has been duly given pursuant to this Indenture or provision therefor satisfactory to the Trustee has been made; and

(iii) Notes which have been cancelled pursuant to Section 2.13 or in exchange for or in lieu of which other Notes have been authenticated and delivered pursuant to this Indenture, other than any such Notes in respect of which there shall have been presented to the Trustee proof satisfactory to it that such Notes are held by a bona fide purchaser in whose hands such Notes are valid obligations of the Company;

provided, however, that in determining whether the Holders of the requisite principal amount of the Outstanding Notes have given any request, demand, authorization, direction, notice, consent or waiver hereunder, Notes owned by the Company or any other obligor upon the Notes or any Affiliate of the Company or of such other obligor shall be disregarded and deemed not to be Outstanding, except that, in

determining whether the Trustee shall be protected in relying upon any such request, demand, authorization, direction, notice, consent or waiver, only Notes which the Trustee knows to be so owned shall be so disregarded. Notes so owned which have been pledged in good faith may be regarded as Outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee’s right so to act with respect to such Notes and that the pledgee is not the Company or any other obligor upon the Notes or any Affiliate of the Company or of such other obligor.

“Pari Passu Indebtedness” means, with respect to any Excess Proceeds from Asset Sales, Indebtedness of the Company or any Subsidiary Guarantor that ranks equally in right of payment with the Notes or the Subsidiary Guarantees, as the case may be, and the terms of which require the Company or any of its Restricted Subsidiaries to apply such Excess Proceeds to offer to repurchase such Indebtedness.

“Permitted Acquisition Indebtedness” means Indebtedness or Disqualified Stock of the Company or any of its Restricted Subsidiaries to the extent such Indebtedness or Disqualified Stock was Indebtedness or Disqualified Stock of any other Person existing at the time (a) such Person became a Restricted Subsidiary of the Company, (b) such Person was merged or consolidated with or into the Company or any of its Restricted Subsidiaries, or (c) assets of such Person were acquired by the Company or any of its Restricted Subsidiaries and such Indebtedness was assumed in connection therewith (excluding any such Indebtedness that is repaid contemporaneously with such event), provided that on the date such Person became a Restricted Subsidiary of the Company or the date such Person was merged or consolidated with or into the Company or any of its Restricted Subsidiaries, or on the date of such asset acquisition, as applicable, either

(1) immediately after giving effect to such transaction on a pro forma basis as if the same had occurred at the beginning of the applicable four-quarter period, the Company or such Restricted Subsidiary, as applicable, would be permitted to incur at least $1.00 of additional Indebtedness pursuant to the Fixed Charge Coverage Ratio test set forth in the first paragraph of Section 4.11,

(2) immediately after giving effect to such transaction on a pro forma basis as if the same had occurred at the beginning of the applicable four-quarter period, the Fixed Charge Coverage Ratio of the Company would be equal to or greater than the Fixed Charge Coverage Ratio of the Company immediately prior to such transaction, or

(3) immediately after giving effect to such transaction on a pro forma basis, the Consolidated Net Worth of the Company would be greater than the Consolidated Net Worth of the Company immediately prior to such transaction.

“Permitted Business Investments” means Investments made in the ordinary course of, and of a nature that is or shall have become customary in, the Oil and Gas Business, including investments or expenditures for actively exploring for, acquiring, developing, producing, processing, gathering, marketing or transporting Hydrocarbons through agreements, transactions, interests or arrangements that permit one to share risk or costs, comply with regulatory requirements regarding local ownership or satisfy other objectives customarily achieved through the conduct of the Oil and Gas Business jointly with third parties, including without limitation:

(1) direct or indirect ownership of crude oil, natural gas, other related Hydrocarbon properties or any interest therein, gathering, transportation, processing, storage or related systems, or ancillary real property interests and interests therein; and

(2) the entry into operating agreements, joint ventures, processing agreements, working interests, royalty interests, mineral leases, farm-in agreements, farm-out agreements, development agreements, production sharing agreements, area of mutual interest agreements, contracts for the sale, transportation or exchange of crude oil and natural gas and related Hydrocarbons and minerals, unitization agreements, pooling arrangements, joint bidding agreements, service contracts, partnership agreements (whether general or limited), or other similar or customary agreements, transactions, properties, interests or arrangements, and Investments and expenditures in connection therewith or pursuant thereto, in each case made or entered into in the ordinary course of the Oil and Gas Business, excluding, however, Investments in corporations and publicly-traded limited partnerships.

“Permitted Holders” means (1) the Company or any Subsidiary of the Company, as long as such Subsidiary of the Company remains a Subsidiary following completion of the transaction that would have constituted a Change of Control, had the transaction not been effected with a Permitted Holder and (2) the directors, officers and other management employees of the Company that are shareholders of the Company on the Initial Issuance Date and their respective Affiliates.

(3) any Investment by the Company or any Restricted Subsidiary of the Company in a Person, if as a result of such Investment:

(b) such Person is merged, consolidated or amalgamated with or into, or transfers or conveys substantially all of its assets to, or is liquidated into, the Company or a Restricted Subsidiary of the Company;

(4) any Investment made as a result of the receipt of non-cash consideration from, or consisting of any deferred portion of the sales price received by the Company or any Restricted Subsidiary in connection with:

(a) an Asset Sale that was made pursuant to and in compliance with Section 4.12;

(b) pursuant to clause (8) of the items deemed not to be Asset Sales under the definition of “Asset Sale;”

(5) any Investment in any Person solely in exchange for, or with the net cash proceeds from a substantially concurrent (i) contribution (other than from a Restricted Subsidiary of the Company) to the equity capital of the Company or (ii) issuance of, Equity Interests (other than Disqualified Stock) of the Company, with an issuance being deemed substantially concurrent of such Investment occurring not more than 120 days after such issuance; provided that the amount of any such net cash proceeds will be excluded from clause (II) of Section 4.09;

(6) any Investments received in compromise or resolution of, or upon satisfaction of judgments with respect to, (a) obligations of trade creditors or customers that were incurred in the ordinary course of business, including pursuant to any plan of reorganization or similar arrangement upon the bankruptcy or insolvency of any trade creditor or customer, or (b) litigation, arbitration or other disputes (including pursuant to any bankruptcy or insolvency proceedings) with Persons who are not Affiliates;

(8) guarantees by the Company or any of its Restricted Subsidiaries of operating leases (other than Capital Lease Obligations) or of other obligations that do not constitute Indebtedness, in each case entered into by the Company or any Restricted Subsidiary of the Company in the ordinary course of business or otherwise customary in the Oil and Gas Business;

(9) Investments in property, plant and equipment used in the ordinary course of business and Permitted Business Investments;

(11) Investments in any Person to the extent such Investments consist of prepaid expenses, negotiable instruments held for collection and lease, utility and workers’ compensation, performance and other similar deposits made in the ordinary course of business by the Company or any of its Restricted Subsidiaries;

(12) guarantees of performance or other obligations (other than Indebtedness) arising in the ordinary course in the Oil and Gas Business, including obligations under oil and natural gas exploration, development, joint operating and related agreements and licenses or concessions related to the Oil and Gas Business;

(13) loans or advances to officers, directors, employees or consultants made in the ordinary course of business or otherwise customary in the Oil and Gas Business and otherwise in compliance with Section 4.13 of this Indenture;

(14) Investments of a Restricted Subsidiary acquired after the Initial Issuance Date or of any entity merged into or consolidated with the Company or a Restricted Subsidiary in accordance with Section 5.01 of this Indenture, the extent that such Investments were not made in contemplation of or in connection with such acquisition, merger or consolidation and were in existence on the date of such acquisition, merger or consolidation;

(15) Investments received as a result of a foreclosure by, or other transfer of title to, the Company or any of its Restricted Subsidiaries with respect to any secured Investment in default;

(16) Liens of the type described in clause (9) of the definition of “Permitted Liens;” and

(17) other Investments having an aggregate Fair Market Value (measured on the date each such Investment was made and without giving effect to subsequent changes in value), when taken together with all other Investments made pursuant to this clause (17) that are at the time outstanding, not to exceed the greater of $30.0 million and 3.0% of the Company’s Adjusted Consolidated Net Tangible Assets determined at the time of such Investment (after giving effect to any dividends, interest payments, return of capital and subsequent reduction in the amount of any Investment made pursuant to this clause (17) as a result of the repayment or other disposition thereof, in an amount not to exceed the amount of such Investments previously made pursuant to this clause); provided, however, that if any Investment pursuant to this clause (17) is made in any Person that is not a Restricted Subsidiary of the Company at the date of the making of such Investment and such Person becomes a Restricted Subsidiary of the Company after such date, such Investment shall thereafter be deemed to have been made pursuant to clause (1) above and shall cease to have been made pursuant to this clause (17) for so long as such Person continues to be a Restricted Subsidiary;

provided, however, that with respect to any Investment, the Company may, in its sole discretion, allocate all or any portion of any Investment and later re-allocate all or any portion of any Investment to one or more of the above clauses (1) through (17) so that the entire Investment would be a Permitted Investment.

(1) Liens securing any Indebtedness and other Obligations under any of the Credit Facilities incurred under clause (1) of the second paragraph of Section 4.11 of this Indenture;

(3) Liens on property (including Capital Stock) of a Person existing at the time such Person is merged with or into or consolidated with the Company or any Restricted Subsidiary of the Company, provided that such Liens were in existence prior to the contemplation of such merger or consolidation and do not extend to any assets other than those of the Person merged into or consolidated with the Company or the Restricted Subsidiary;

(4) Liens on property existing at the time of acquisition of the property by the Company or any Restricted Subsidiary of the Company, provided that such Liens were in existence prior to the contemplation of such acquisition;

(5) any interest or title of a lessor to the property subject to a Capital Lease Obligation;

(6) Liens on any asset or property acquired, constructed or improved by the Company or any of its Restricted Subsidiaries; provided that (a) such Liens are in favor of the seller of such asset or property, in favor of the Person or Persons developing, constructing, repairing or improving such asset or property, or in favor of the Person or Persons that provided the funding for the acquisition, development, construction, repair or improvement cost, as the case may be, of such asset or property, (b) such Liens are created within 360 days after the acquisition, development, construction, repair or improvement, (c) the aggregate principal amount of the Indebtedness secured by such Liens is otherwise permitted to be incurred under this Indenture and does not exceed the greater of (i) the cost of the asset or property so acquired, constructed or improved plus related financing costs and (ii) the Fair Market Value (as determined by an executive officer involved in or otherwise familiar with such acquisition, construction or improvement of such asset or property, or, if such Fair Market Value is $40.0 million or more, the Board of Directors of the Company) of the asset or property so acquired, constructed or improved, measured at the date of such acquisition, or the date of completion of such construction or improvement, and (d) such Liens are limited to the asset or property so acquired, constructed or improved (including the proceeds thereof, accessions thereto, upgrades thereof and improvements thereto);

(7) Liens existing on the Initial Issuance Date other than Liens securing the Credit Facilities;

(8) Liens to secure the performance of tenders, bids, statutory obligations, surety or appeal bonds, government contracts, performance bonds or other obligations of a like nature incurred in the ordinary course of business;

(9) Liens on and pledges of the Equity Interests of any Unrestricted Subsidiary or any Joint Venture owned by the Company or any Restricted Subsidiary of the Company to the extent securing Non-Recourse Debt or other Indebtedness of such Unrestricted Subsidiary or Joint Venture;

(12) Liens arising under oil and gas leases, overriding royalty interest agreements, operating agreements, joint venture agreements, partnership agreements, oil and gas leases, farm-out agreements, farm-in agreements, division orders, contracts for the sale, transportation or exchange of crude oil and natural gas and related Hydrocarbons and minerals, unitization and pooling declarations and agreements, area of mutual interest agreements, land purchase option arrangements, participation and development agreements, joint operating agreements, and other agreements (including, without limitation, options, put and call arrangements, rights of first offer, rights of first refusal, preferential rights, restrictions on dispositions and the like and those of the type described in the definition of “Permitted Business Investments”) arising in the ordinary course of business of the Company and its Restricted Subsidiaries or that are customary in the Oil and Gas Business;

(13) Liens reserved in oil and gas mineral leases for bonus or rental payments and for compliance with the terms of such leases;

(14) Liens upon specific items of inventory, receivables or other goods or proceeds of the Company or any of its Restricted Subsidiaries securing such Person’s obligations in respect of bankers’ acceptances or receivables securitizations issued or created for the account of such Person to facilitate the purchase, shipment or storage of such inventory, receivables or other goods or proceeds and permitted by Section 4.11;

(15) Liens securing Obligations of the Company or the Subsidiary Guarantors under the Notes or the Subsidiary Guarantees, as the case may be, and Liens securing other obligations of the Company or the Subsidiary Guarantors under this Indenture (other than with respect to Securities other than the Notes);

(16) Liens to secure payment and performance of Hedging Contracts of the Company or any of its Restricted Subsidiaries;

(17) Liens for taxes, assessments or governmental charges or claims that are not yet delinquent by more than sixty (60) days or that are being contested in good faith by appropriate proceedings promptly instituted and diligently concluded; provided that any reserve or other appropriate provision as is required in conformity with GAAP has been made therefor;

(18) landlords’, carriers’, warehousemen’s, mechanics’, materialmen’s, repairmen’s or like Liens arising by contract or statute in the ordinary course of business and with respect to amounts which are not yet delinquent by more than sixty (60) days or are being contested in good faith by appropriate proceedings;

(19) pledges or deposits made in the ordinary course of business (A) in connection with leases, tenders, bids, statutory obligations, surety or appeal bonds, government contracts, performance bonds and similar obligations, or (B) in connection with workers’ compensation, unemployment insurance and other social security or similar legislation;

(20) any attachment or judgment Lien that does not constitute an Event of Default;

(21) survey exceptions, easements or reservations of, or rights of others for, licenses, rights-of-way, sewers, electric lines, telegraph and telephone lines and other similar purposes, or zoning or other restrictions as to the use of real property that were not incurred in connection with Indebtedness and that do not in the aggregate materially adversely affect the value of said properties or materially impair their use in the operation of the business of the Company or any of its Restricted Subsidiaries;

(22) Liens arising solely by virtue of any statutory or common law provisions relating to banker’s Liens, rights of set-off or similar rights and remedies as to deposit accounts or other funds maintained or deposited with a depositary institution; provided that (A) such deposit account is not a dedicated cash collateral account and is not subject to restrictions against access by the Company in excess of those set forth by regulations promulgated by the Federal Reserve Board and (B) such deposit account is not intended by the Company or any of its Restricted Subsidiaries to provide collateral to the depositary institution;

(23) Liens arising from Uniform Commercial Code financing statement filings regarding operating leases entered into by the Company and its Restricted Subsidiaries in the ordinary course of business;

(24) leases or subleases granted to others that do not materially interfere with the ordinary course of business of the Company and its Restricted Subsidiaries, taken as a whole;

(25) Liens arising under this Indenture or any supplemental indenture to the Original Indenture in favor of the Trustee for its own benefit and similar Liens in favor of other trustees, agents and representatives arising under instruments governing Indebtedness permitted to be incurred under this Indenture; provided, however, that such Liens are solely for the benefit of the trustees, agents or representatives in their capacities as such and not for the benefit of the holders of such Indebtedness;

(26) Liens arising from the deposit of funds or securities in trust for the purpose of decreasing or defeasing Indebtedness so long as such deposit of funds or securities and such decreasing or defeasing of Indebtedness are permitted under Section 4.09 of this Indenture;

(27) Liens (other than Liens securing Indebtedness) on, or related to, assets to secure all or part of the costs incurred in the ordinary course of the Oil and Gas Business for the exploration, drilling, development, production, processing, transportation, marketing, storage or operation thereof;

(28) Liens arising from royalties, overriding royalties, revenue interests, net revenue interests, net profit interests, reversionary interests, production payments, preferential rights of purchase, working interests and other similar interests, all as ordinarily exist with respect to properties and assets of the Company and its Restricted Subsidiaries or otherwise as are customary in the Oil and Gas Business;

(29) Liens incurred in the ordinary course of business of the Company or any Restricted Subsidiary of the Company, provided that, after giving effect to any such incurrence, the aggregate principal amount of all Indebtedness then outstanding and secured by any Liens incurred pursuant to this clause (29) does not exceed the amount set forth in clause (18) of the second paragraph of Section 4.11 of this Indenture; and

(30) Liens to secure any Permitted Refinancing Indebtedness permitted to be incurred under this Indenture and incurred to refinance Indebtedness that was previously so secured other than Indebtedness referred to in clause (1) above, provided that any such Lien is limited to all or part of the same assets (plus improvements, accessions, proceeds or dividends or distributions in respect thereof) that secured (or, under the written arrangements under which the original Lien arose, could secure) the Indebtedness being refinanced or is in respect of assets that is the security for a Permitted Lien hereunder.

“Permitted MLP Securities” means equity securities (including incentive distribution rights) of a master limited partnership (or limited liability company or similar business entity with pass-through treatment for U.S. Federal income tax purposes) that has a class of equity securities traded on the New York Stock Exchange, the NYSE Amex, the NASDAQ Stock Market or any successor to any such exchange or market, provided that such master limited partnership (or other entity) is an Affiliate of the Company.

“Permitted Refinancing Indebtedness” means any Indebtedness of the Company or any of its Restricted Subsidiaries or any Disqualified Stock of the Company incurred or issued in exchange for, or the net proceeds of which shall be used to extend, refinance, renew, replace, defease, discharge, refund or otherwise retire for value, in whole or in part, any other Indebtedness of the Company or any of its Restricted Subsidiaries (other than intercompany Indebtedness) or any Disqualified Stock of the Company (the “Refinanced Indebtedness”), provided that:

(1) the principal amount, or in the case of Disqualified Stock, the amount thereof as determined in accordance with the definition of Disqualified Stock, of such Permitted Refinancing Indebtedness does not exceed the principal amount of the Refinanced Indebtedness (plus all accrued (including, for the purposes of defeasance, future accrued) and unpaid interest on, or accrued and unpaid dividends on, the Refinanced Indebtedness, as the case may be, and the amount of all fees, expenses and premiums incurred in connection therewith) and by an amount equal to any existing commitments and incremental facilities unutilized thereunder to the extent incurrence of indebtedness under such unutilized commitment and incremental facilities would then have been permitted;

(2) such Permitted Refinancing Indebtedness has a final maturity date or redemption date, as applicable, later than or equal to the shorter of (A) 91 days following the Stated Maturity of the Notes or (B) the final maturity date or redemption date, as applicable, of, the Refinanced Indebtedness;

(3) such Permitted Refinancing Indebtedness has a Weighted Average Life to Maturity at the time such Permitted Refinancing Indebtedness is incurred equal to or greater than the shorter of (A) the Weighted Average Life to Maturity of, the Refinanced Indebtedness and (B) the Weighted Average Life to Maturity that would result if all payments of principal on the Refinanced Indebtedness that were due on or after the date that is 91 days following the last maturity date of any Notes then Outstanding were instead due on such date;

(4) if the Refinanced Indebtedness is contractually subordinated or otherwise junior in right of payment to the Notes or the Subsidiary Guarantees, such Permitted Refinancing Indebtedness is contractually subordinated or otherwise junior in right of payment to the Notes or the Subsidiary Guarantees on terms at least as favorable to the Holders of Notes as those contained in the documentation governing the Refinanced Indebtedness; and

(5) such Permitted Refinancing Indebtedness is not incurred (other than by way of a guarantee) by a Non-Guarantor Restricted Subsidiary of the Company if the Company or a Subsidiary Guarantor is the issuer or other obligor on the Refinanced Indebtedness; and

(6) except as otherwise provided in clause (3) of the second paragraph of Section 4.09, the proceeds of the Permitted Refinancing Indebtedness shall be used substantially concurrently with the incurrence thereof to extend, refinance, renew, replace, defease, discharge, refund or otherwise retire the Refinanced Indebtedness, unless the Refinanced Indebtedness is not then due and is not redeemable or prepayable, defeasable or dischargeable, as the case may be, at the option of the obligor thereof or is redeemable or prepayable or may be defeased or discharged only with notice, in which case, such proceeds shall be held in a segregated account of the obligor of the Refinanced Indebtedness until the Refinanced Indebtedness becomes due or redeemable, prepayable or subject to defeasance or discharge, as the case may be, or such notice period lapses and then shall be used to extend, refinance, renew, replace, defease, discharge, refund or otherwise retire the Refinanced Indebtedness; provided that in any event the Refinanced Indebtedness shall be extended, refinanced, renewed, replaced, defeased, discharged, refunded or otherwise retired within 60 days of the incurrence of the Refinancing Indebtedness.

“Person” means any individual, corporation, partnership, joint venture, association, joint-stock company, trust, unincorporated organization, limited liability company or government or other entity.

“Production Facility or Pipeline Assets” means (i) assets used primarily for production gathering, transmission, transportation, storage, processing or treatment of natural gas, natural gas liquids or other Hydrocarbons or carbon dioxide and (ii) equity interests of any Person that has no substantial assets other than assets referred to in clause (i).

“Production Payments” means, collectively, Dollar-Denominated Production Payments and Volumetric Production Payments.

“Production Payments and Reserve Sales” means the grant or transfer by the Company or a Restricted Subsidiary of the Company to any Person of a royalty, overriding royalty, net profits interest, production payment (whether volumetric or dollar denominated), partnership or other interest in oil and gas properties, reserves or the right to receive all or a portion of the production or the proceeds from the sale of production attributable to such properties, including any such grants or transfers pursuant to incentive compensation programs on terms that are reasonably customary in the oil and gas business for geologists, geophysicists and other providers of technical services to the Company or a Subsidiary of the Company.

“Rating Agency” means S&P and Moody’s, or if S&P or Moody’s or both shall not make a rating on the Notes publicly available, a nationally recognized statistical rating agency or agencies, as the case may be, selected by the Company (as certified by a resolution of the Board of Directors or a committee thereof) which shall be substituted for S&P or Moody’s or both, as the case may be.

“Reporting Default” means a Default described in clause (4) of Section 6.01.

“Restricted Investment” means an Investment other than a Permitted Investment.

“Restricted Subsidiary” of a Person means any Subsidiary of the referent Person that is not an Unrestricted Subsidiary.

“S&P” means Standard & Poor’s Ratings Services, a division of The McGraw-Hill Companies, Inc., or any successor to the rating agency business thereof.

“Sale Leaseback Transaction” means, with respect to the Company or any of its Restricted Subsidiaries, any arrangement with any Person providing for the leasing by the Company or any of its Restricted Subsidiaries of any principal property, acquired or placed into service more than 180 days prior to such arrangement, whereby such property has been or is to be sold or transferred by the Company or any of its Restricted Subsidiaries to such Person.

(1) all Indebtedness of the Company or any of its Restricted Subsidiaries outstanding under the Credit Agreement and all obligations under Hedging Contracts with respect thereto;

(2) any other Indebtedness of the Company or any of its Restricted Subsidiaries permitted to be incurred under the terms of this Indenture, unless the instrument under which such Indebtedness is incurred expressly provides that it is subordinated in right of payment to the Notes or any Subsidiary Guarantee; and

(3) all Obligations with respect to the items listed in the preceding clauses (1) and (2).

Notwithstanding anything to the contrary in the preceding sentence, Senior Debt will not include:

(a) any intercompany Indebtedness of the Company or any of its Restricted Subsidiaries to the Company or any of its Affiliates; or

For the avoidance of doubt, “Senior Debt” will not include any trade payables or taxes owed or owing by the Company or any of its Restricted Subsidiaries.

“Significant Subsidiary” means any Subsidiary that would be a “significant subsidiary” as defined in Article 1, Rule 1-02 of Regulation S-X, promulgated pursuant to the Securities Act, as such Regulation is in effect on the Initial Issuance Date.

“Stated Maturity” means, with respect to any installment of interest or principal on any series of Indebtedness, the date on which the payment of interest or principal was scheduled to be paid in the original documentation governing such Indebtedness, and will not include any contingent obligations to repay, redeem or repurchase any such interest or principal prior to the date originally scheduled for the payment thereof.

(1) any corporation, association or other business entity (other than a partnership or limited liability company) of which more than 50% of the total voting power of Voting Stock is at the time owned or controlled, directly or indirectly, by that Person or one or more of the other Subsidiaries of that Person (or a combination thereof); and

(2) any partnership (whether general or limited) or limited liability company (a) the sole general partner or member of which is such Person or a Subsidiary of such Person, or (b) if there is more than a single general partner or member, either (x) the only managing general partners or managing members of which are such Person or one or more Subsidiaries of such Person (or any combination thereof) or (y) such Person owns or controls, directly or indirectly, a majority of the outstanding general partner interests, member interests or other Voting Stock of such partnership or limited liability company, respectively.

“Subsidiary Guarantee” means the joint and several guarantee pursuant to Article X hereof by a Subsidiary Guarantor of the Obligations of the Company under this Indenture and the Notes.

“Subsidiary Guarantors” means each of (a) the Restricted Subsidiaries of the Company executing this Indenture as initial Subsidiary Guarantors, (b) any other Restricted Subsidiary of the Company that executes a supplement to this Indenture in accordance with Section 4.15 or 10.02 hereof and (c) the respective successors and assigns of such Restricted Subsidiaries, in each case until such time as any such Restricted Subsidiary shall be released and relieved of its obligations pursuant to Section 4.15, 8.01 or 10.03 hereof.

“Successor Parent” with respect to any Person means any other Person more than 50% of the total outstanding Voting Stock of which (measured by voting power rather than the number of shares, units or the like) is, at the time the first Person becomes a Subsidiary of such other Person, “Beneficially Owned” either by the first Person or by one or more Persons that Beneficially Owned more than 50% of the total outstanding Voting Stock of the first Person (measured by voting power rather than the number of shares, units or the like) immediately prior to the first Person becoming a Subsidiary of such other Person.

“Treasury Rate” means, as of any Redemption Date, the yield to maturity as of such Redemption Date of United States Treasury securities with a constant maturity (as compiled and published in the most recent Federal Reserve Statistical Release H.15(519) which has become publicly available at least two Business Days prior to the Redemption Date (or, if such Statistical Release is no longer published, any publicly available source of similar market data)) most nearly equal to the period from the Redemption Date to April 15, 2018; provided, however, that if such period is not equal to the constant maturity of a United States Treasury security for which a weekly average yield is given, the Company shall obtain the Treasury Rate by linear interpolation (calculated to the nearest one-twelfth of a year) from the weekly average yields of United States Treasury securities for which such yields are given, except that if the period from the Redemption Date to April 15, 2018 is less than one year, the weekly average yield on actually traded United States Treasury securities adjusted to a constant maturity of one year shall be used. The Company will (a) calculate the Treasury Rate on the second Business Day preceding the applicable Redemption Date and (b) prior to such Redemption Date file with the Trustee an Officers’ Certificate setting forth the Make Whole Premium and the Treasury Rate and showing the calculation of each in reasonable detail.

“Uniform Commercial Code” means the New York Uniform Commercial Code as in effect from time to time.

“Unrestricted Subsidiary” means, initially, Monument Exploration LLC, and thereafter shall include any Subsidiary of the Company that is designated by the Board of Directors of the Company as an Unrestricted Subsidiary pursuant to a Board Resolution, but only to the extent that such Subsidiary:

(1) has no Indebtedness other than Non-Recourse Debt owing to any Person other than the Company or any of its Restricted Subsidiaries;

(2) is not party to any agreement, contract, arrangement or understanding with the Company or any Restricted Subsidiary of the Company unless (a) the terms of any such agreement, contract, arrangement or understanding are no less favorable to the Company or such Restricted Subsidiary than those that might be obtained at the time from Persons who are not Affiliates of the Company or (b) is otherwise permitted under the provisions of Section 4.13 or (c) to the extent that clause (a) or (b) is not satisfied, the excess value of such agreement, contract, arrangement or understanding shall be deemed a Restricted Payment;

(3) is a Person with respect to which neither the Company nor any of its Restricted Subsidiaries has any direct or indirect obligation (a) to subscribe for additional Equity Interests or (b) to maintain or preserve such Person’s financial condition or to cause such Person to achieve any specified levels of operating results; and

(4) has not, from and after such designation, guaranteed or otherwise directly or indirectly provided credit support for any Indebtedness of the Company or any of its Restricted Subsidiaries (other than as otherwise provided in the definition of “Non-Recourse Debt”);

provided, however, that items (1) through (4) above shall not be deemed to prevent Permitted Investments in Unrestricted Subsidiaries that are otherwise allowed under this Indenture.

Any designation of a Subsidiary of the Company as an Unrestricted Subsidiary will be evidenced to the Trustee by filing with the Trustee a Board Resolution giving effect to such designation and an Officers’ Certificate certifying that such designation complied with the preceding conditions and was permitted by Section 4.09. 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 the Indenture, such designation shall be deemed to have occurred for all purposes of the 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 and any Indebtedness of such Subsidiary will be deemed to be incurred by a Restricted Subsidiary of the Company as of such date and, if such Indebtedness is not permitted to be incurred as of such date under Section 4.11, the Company will be in default of such covenant.

“Volumetric Production Payments” means production payment obligations recorded as deferred revenue in accordance with GAAP, together with all related undertakings and obligations.

“Voting Stock” of any Person as of any date means the Capital Stock of such Person that is at the time entitled (without regard to the occurrence of any contingency) to vote in the election of the Board of Directors of such Person.

“Weighted Average Life to Maturity” means, when applied to any Indebtedness or Disqualified Stock at any date, the number of years obtained by dividing:

(1) the sum of the products obtained by multiplying (a) the amount of each then remaining installment, sinking fund, serial maturity or other required payments of principal, including payment at final maturity or redemption, in respect of the Indebtedness or Disqualified Stock, by (b) the number of years (calculated to the nearest one-twelfth) that will elapse between such date and the making of such payment; by

(2) the then outstanding aggregate principal amount of such Indebtedness or Disqualified Stock.

Section 1.02 of the Original Indenture shall be amended by inserting the following terms, in their appropriate alphabetical position, and corresponding section references into the table in such Section 1.02 of the Original Indenture:

The Original Indenture shall be amended by replacing the second sentence of Section 2.09 of the Original Indenture with the following sentence:

If any such mutilated, destroyed, lost or stolen Security has become or is about to become due and payable, or is about to be redeemed or purchased by the Company pursuant to an optional redemption described in Section 3.12 or purchased by the Company upon a Change of Control or an Asset Sale pursuant to Article IV, the Company in its discretion may, instead of issuing a new Security, pay, redeem or purchase such Security.

Clause (8) of Section 9.01 of the Original Indenture is hereby amended to replace the words “prospectus supplement” with the words “prospectus, prospectus supplement or offering memorandum.”

Article V of the Original Indenture shall be amended by replacing Article V of the Original Indenture with the following with respect to the Notes:

The Company may not (x) consolidate or merge with or into another Person (whether or not the Company is the survivor), or (y) directly or indirectly sell, assign, transfer, lease, convey or otherwise dispose of all or substantially all of its assets, in one or more related transactions to another Person, unless:

(a) either (1) the Company is the survivor or (2) the Person formed by or surviving any such consolidation or merger (if other than the Company) or to which such sale, assignment, transfer, lease, conveyance or other disposition shall have been made is a Person organized or existing under the laws of the United States, any state of the United States or the District of Columbia;

(b) the Person formed by or surviving any such consolidation or merger (if other than the Company) or the Person to which such sale, assignment, transfer, lease, conveyance or other disposition shall have been made assumes all the obligations of the Company under the Notes and this Indenture pursuant to a supplemental indenture or other agreement in a form reasonably satisfactory to the Trustee;

(i) the Company or the Person formed by or surviving any such consolidation or merger (if other than the Company), or to which such sale, assignment, transfer, lease, conveyance or other disposition shall have been made will, on the date of such transaction immediately after giving pro forma effect thereto and any related financing transactions as if the same had occurred at the beginning of the applicable four-quarter period, be permitted to incur at least $1.00 of additional Indebtedness pursuant to the Fixed Charge Coverage Ratio test set forth in the first paragraph of Section 4.11 hereof; or

(ii) immediately after giving effect to such transaction and any related financing transactions on a pro forma basis as if the same had occurred at the beginning of the applicable four-quarter period, the Fixed Charge Coverage Ratio of the Company or the Person formed by or surviving any such consolidation or merger (if other than the Company), or to which such sale, assignment, transfer, lease, conveyance or other disposition has been made, will be equal to or greater than the Fixed Charge Coverage Ratio of the Company immediately prior to such transaction; or

(iii) immediately after giving effect to such transaction and any related financing transactions on a pro forma basis, the Consolidated Net Worth of the Company will be greater than the Consolidated Net Worth of the Company immediately prior to such transaction; and

(e) the Company has delivered to the Trustee an Officers’ Certificate and an Opinion of Counsel, each stating that such consolidation, merger or disposition and such supplemental indenture (if any) comply with this Indenture.

Notwithstanding the restrictions described in the foregoing clauses (c) and (d), (x) any Restricted Subsidiary of the Company may consolidate with, merge into or dispose of all or part of its assets to the Company or another Restricted Subsidiary, and (y) the Company may merge with or into an Affiliate formed solely for the purpose of reincorporating the Company in another jurisdiction, and the Company will not be required to comply with the preceding clause (e) in connection with any such consolidation, merger or disposition.

For purposes of the foregoing, the transfer (by lease, assignment, sale or otherwise, in a single transaction or series of transactions) of all or substantially all of the assets of one or more Restricted Subsidiaries of the Company, the Capital Stock of which constitutes all or substantially all of the assets of the Company, shall be deemed to be the transfer of all or substantially all of the assets of the Company.

Upon any consolidation or merger, or any sale, assignment, transfer, lease, conveyance or other disposition of all or substantially all of the assets of the Company in accordance with Section 5.01 hereof, in which the Company is not the surviving entity, the surviving entity formed by such consolidation or into or with which the Company is merged or to which such sale, assignment, transfer, lease, conveyance or

other disposition is made shall succeed to, and be substituted for, and may exercise every right and power of, the Company under this Indenture with the same effect as if such surviving entity had been named as the Company herein and shall be substituted for the Company (so that from and after the date of such consolidation, merger, sale, assignment, transfer, lease, conveyance or other disposition, the provisions of this Indenture referring to the “Company” shall refer instead to the surviving entity and not to the Company); and thereafter (except in the case of a lease of all or substantially all of the Company’s assets), the Company shall be discharged and released from all obligations and covenants under this Indenture and the Notes. The Trustee shall enter into a supplemental indenture to evidence the succession and substitution of such successor and such discharge and release of the Company.

Article II of the Original Indenture shall be amended by inserting the following section:

The Company shall be entitled, subject to its compliance with Section 4.11, at any time and from time to time, and without notice or consent of the Holders of the Notes, to create and issue Additional Notes under this Indenture which shall rank equally and ratably with, and have substantially identical terms, as the Notes issued on the Initial Issuance Date, other than with respect to the date of issuance and issue price; provided, however, that any issuance of Additional Notes bearing the same CUSIP number as the Notes issued on the Initial Issuance Date (i) is treated as part of the same issue as the Notes issued on the Initial Issuance Date within the meaning of Treasury Regulation § 1.1275-1(f), (ii) is a qualified reopening of the Notes issued on the Initial Issuance Date within the meaning of Treasury Regulation § 1.1275-2(k), or (iii) is otherwise fungible with the Notes issued on the Initial Issuance Date for U.S. federal income tax purposes, in the case of each of clauses (i), (ii) and (iii), so that such Additional Notes will trade as part of a single class with the Notes issued on the Initial Issuance Date, and provided further that Additional Notes that do not fall within clause (i), (ii) or (iii) of this paragraph shall have separate CUSIP and ISIN numbers. The Notes issued on the Initial Issuance Date, and any Additional Notes shall be treated as a single class for all purposes under this Indenture, including, without limitation, waivers, consents, directions, declarations, amendments, redemptions and offers to purchase.

With respect to any Additional Notes, the Company shall set forth in an Officers’ Certificate, which shall be delivered to the Trustee, the following information:

(1) the aggregate principal amount of such Additional Notes to be authenticated and delivered pursuant to this Indenture; and

(2) the issue price, the issue date (and the corresponding date from which interest shall accrue thereon and the first interest payment date therefor) and the CUSIP number and any corresponding ISIN of such Additional Notes.

(a) Section 3.03 of the Original Indenture shall be amended by replacing that section of the Original Indenture with the following with respect to the Notes:

If less than all of the Notes are to be redeemed at any time, the Trustee shall select the Notes to be redeemed among the Holders of the Notes as follows: (1) if the Notes are listed on any national securities exchange, in compliance with the requirements of the principal national securities exchange on which the Notes are listed; or (2) if the Notes are not listed on any national securities exchange, on a pro rata basis or, in the case of Notes in global form, the Trustee will select Notes for redemption based on DTC’s method that most nearly approximates pro rata selection unless otherwise required by law. In the event of partial

redemption other than on a pro rata basis, the particular Notes to be redeemed shall be selected, not less than five (5) Business Days (unless a shorter period shall be agreeable to the Trustee) prior to the giving of notice of the redemption pursuant to Section 3.04, by the Trustee from the Outstanding Notes not previously called for redemption.

The Trustee shall promptly notify the Company in writing of the Notes selected for redemption and, in the case of any Note selected for partial redemption, the principal amount thereof to be redeemed. Notes and portions of Notes selected shall be in amounts of $2,000 or whole multiples of $1,000 in excess of $2,000; except that if all of the Notes of a Holder are to be redeemed, the entire Outstanding amount of Notes held by such Holder, even if not a multiple of $1,000, shall be redeemed. Provisions of this Indenture that apply to Notes called for redemption also apply to portions of Notes called for redemption.

(b) The first paragraph of Section 3.04 of the Original Indenture shall be amended by replacing that paragraph with the following:

Subject to the provisions of Section 3.13 hereof, at least 30 days but not more than 60 days before a Redemption Date (except that redemption notices may be mailed or sent more than 60 days prior to a Redemption Date if the notice is issued in connection with a legal defeasance, covenant defeasance or discharge), the Company shall mail or cause to be mailed, by first class mail, or if the Notes are in global form, sent pursuant to the applicable procedures of DTC, a notice of redemption to each Holder whose Notes are to be redeemed at its registered address. 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 a related Equity Offering.

(a) Except as set forth in clauses (b) and (c) of this Section 3.12 or in the final paragraph of Section 4.16, the Company shall not have the option to redeem the Notes prior to April 15, 2018. On and after April 15, 2018, the Company shall have the option to redeem the Notes, in whole or in part at any time, at the Redemption Prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on the Notes to be redeemed to the applicable Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the Redemption Date), if redeemed during the twelve-month period beginning on April 15 of the years indicated below:

(b) Notwithstanding the provisions of clause (a) of this Section 3.12, at any time prior to April 15, 2018, the Company may on any one or more occasions redeem up to 35% of the aggregate principal amount of Notes (including any Additional Notes) issued under this Indenture at a Redemption Price of 106.250% of the principal amount thereof, plus accrued and unpaid interest, if any, thereon to the Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the Redemption Date), in an amount up to the amount of the net cash proceeds of one or more Equity Offerings, provided that, with respect to each such redemption:

(1) at least 65% of the aggregate principal amount of Notes initially issued under this Indenture remains Outstanding immediately after the occurrence of such redemption (excluding any Notes held by the Company and its Subsidiaries); and

(2) such redemption occurs within 180 days of the date of the closing of the related Equity Offering.

(c) Prior to April 15, 2018, the Company may redeem on one or more occasions all or part of the Notes at a Redemption Price equal to the sum of:

(2) accrued and unpaid interest, if any, to the Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the Redemption Date), plus

(d) Any redemption pursuant to this Section 3.12 shall be made pursuant to the provisions of Section 3.01 through Section 3.11 hereof.

(e) Nothing in this Section 3.12 shall prohibit the Company from acquiring the Notes by means other than a redemption, whether pursuant to a tender offer, open market purchase or otherwise, so long as the acquisition does not violate the terms of the Indenture.

In the event that, pursuant to Section 4.12 hereof, the Company shall be required to commence an offer to all Holders to purchase Notes (an “Asset Sale Offer”), it shall follow the procedures specified below.

The Asset Sale Offer shall remain open for a period of 20 Business Days following its commencement and no longer, except to the extent that a longer period is required by Applicable Law (the “Offer Period”). No later than five Business Days after the termination of the Offer Period (the “Settlement Date”), the Company shall purchase and pay for the principal amount of Notes required to be purchased pursuant to Section 4.12 hereof (the “Offer Amount”) or, if less than the Offer Amount has been tendered, all Notes validly tendered in response to the Asset Sale Offer. Payment for any Notes so purchased shall be made in the manner prescribed in the Notes.

Upon the commencement of an Asset Sale Offer, the Company shall send, by first class mail, a notice to each of the Holders, with a copy to the Trustee. The notice shall contain all instructions and materials necessary to enable such Holders to tender Notes pursuant to the Asset Sale Offer. The Asset Sale Offer shall be made to all Holders. The notice, which shall govern the terms of the Asset Sale Offer, shall state:

(a) that the Asset Sale Offer is being made pursuant to this Section 3.13 and Section 4.12 hereof and the length of time the Asset Sale Offer shall remain open, including the time and date the Asset Sale Offer will terminate (the “Termination Date”);

(d) that, unless the Company defaults in making such payment, any Note accepted for payment pursuant to the Asset Sale Offer shall cease to accrue interest after the Settlement Date;

(e) that Holders electing to have a Note purchased pursuant to any Asset Sale Offer shall be required to surrender the Note, properly endorsed for transfer, together with the form entitled “Option of Holder to Elect Purchase” on the reverse of the Note completed and such customary documents as the Company may reasonably request, to the Company or a Paying Agent at the address specified in the notice, before the Termination Date;

(f) that Holders shall be entitled to withdraw their election if the Company or the Paying Agent, as the case may be, receives, prior to the Termination Date, a telegram, telex, facsimile transmission or letter setting forth the name of the Holder, the principal amount of the Note the Holder delivered for purchase and a statement that such Holder is withdrawing his election to have such Note purchased;

(g) that, if the aggregate principal amount of Notes surrendered by Holders, and Pari Passu Indebtedness surrendered by holders or lenders, collectively, exceeds the amount the Company is required to repurchase, the Trustee shall select the Notes and Pari Passu Indebtedness to be purchased on a pro rata basis on the basis of the aggregate principal amount of tendered Notes and Pari Passu Indebtedness (with such adjustments as may be deemed appropriate by the Trustee so that only Notes in denominations of $2,000, or integral multiples of $1,000 in excess of $2,000, shall be purchased); and

(h) that Holders whose Notes were purchased only in part shall be issued Notes equal in principal amount to the unpurchased portion of the Notes surrendered, which unpurchased portion must be equal to $2,000 in principal amount or an integral multiple of $1,000 in excess of $2,000.

If any of the Notes subject to an Asset Sale Offer is in the form of a Global Note, then the Company shall modify such notice to the extent necessary to accord with the procedures of the Depositary applicable to repurchases.

Promptly after the Termination Date, the Company shall, to the extent lawful, accept for payment Notes or portions thereof tendered pursuant to the Asset Sale Offer in the aggregate principal amount required by Section 4.12 hereof, and prior to the Settlement Date it shall deliver to the Trustee an Officers’ Certificate stating that such Notes or portions thereof were accepted for payment by the Company in accordance with the terms of this Section 3.13 and Section 4.12. Prior to 11:00 a.m., New York City time, on the Settlement Date, the Company or the Paying Agent, as the case may be, shall mail or deliver to each tendering Holder an amount equal to the purchase price of the Notes tendered by such Holder and accepted by the Company for purchase, and the Company shall issue a Note, and the Trustee shall authenticate and mail or deliver such Note to such Holder, in a principal amount equal to any unpurchased portion of the Note surrendered. Any Note not so accepted shall be promptly mailed or delivered by the Company to the Holder thereof. The Company shall publicly announce the results of the Asset Sale Offer on or before the Settlement Date.

(a) Section 4.05 of the Original Indenture is amended and restated in its entirety as follows:

Except as otherwise permitted pursuant to the terms hereof (including consolidation and merger permitted by Section 5.01), the Company shall do or cause to be done all things necessary to preserve and

keep in full force and effect its corporate existence, and the corporate, partnership, limited liability company or other existence of each of its Restricted Subsidiaries, in accordance with the respective organizational documents (as the same may be amended from time to time) of the Company or any such Restricted Subsidiary; provided, however, that the Company shall not be required to preserve the existence of any of its Restricted Subsidiaries if the Company shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Company and its Restricted Subsidiaries taken as a whole and that the loss thereof is not adverse in any material respect to the Holders of the Notes.

(b) Article IV of the Original Indenture is amended by adding the following covenants for the benefit of the Holders of the Notes:

From and after the first day (the “Suspension Date”) on which (i) the Notes have an Investment Grade Rating from both of the Rating Agencies and (ii) no Default has occurred and is continuing under the Indenture, the Company and its Restricted Subsidiaries shall cease to be subject to the provisions of the following sections of the Indenture:

If at any date (each such date, a “Reversion Date”) the credit rating of the Notes is downgraded from an Investment Grade Rating by either Rating Agency, then the Suspended Covenants will thereafter be reinstated and again be applicable pursuant to the terms of the Indenture, unless and until the Notes subsequently attain an Investment Grade Rating. The period of time between any Suspension Date and the first subsequent Reversion Date is referred to herein as a “Suspension Period.” Neither the failure of the Company or any of its Subsidiaries to comply with a Suspended Covenant during a Suspension Period nor compliance by the Company or any of its Subsidiaries with any contractual obligation entered into in compliance with the Indenture during a Suspension Period will constitute a Default, Event of Default or breach of any kind under the Indenture, the Notes or the Subsidiary Guarantees.

During any Suspension Period, the Board of Directors of the Company shall not designate any of the Company’s Subsidiaries as Unrestricted Subsidiaries pursuant to the Indenture.

Calculations made after any Reversion Date of the amount available to be made as Restricted Payments under Section 4.09 will be made as though the covenant described in Section 4.09 had been in effect at all times since the Initial Issuance Date, including during any Suspension Period.

The Company shall provide an Officers’ Certificate to the Trustee indicating the occurrence of any Suspension Date or Reversion Date. The Trustee will have no obligation to (i) independently determine or verify if such events have occurred, (ii) make any determination regarding the impact of actions taken during the Suspension Period on the Company’s and its Subsidiaries’ future compliance with their covenants or (iii) notify the holders of any Suspension Date or Reversion Date.

The Company will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly:

(1) declare or pay any dividend or make any other payment or distribution on account of the Company’s or any of its Restricted Subsidiaries’ Equity Interests (including, without limitation, any payment in connection with any merger or consolidation involving the Company or any of its Restricted Subsidiaries) or to the holders of the Company’s or any of its Restricted Subsidiaries’ Equity Interests in their capacity as such (other than dividends or distributions payable in Equity Interests (other than Disqualified Stock) of the Company or payable to the Company or a Restricted Subsidiary of the Company);

(2) purchase, redeem or otherwise acquire or retire for value (including, without limitation, in connection with any merger or consolidation involving the Company) any Equity Interests of the Company or any direct or indirect parent of the Company;

(3) make any principal payment on or with respect to, or purchase, redeem, defease or otherwise acquire or retire for value any Indebtedness that is subordinated in right of payment to the Notes or any Subsidiary Guarantee (excluding (a) any intercompany Indebtedness between or among the Company and any of its Restricted Subsidiaries, (b) the purchase, redemption, defeasance, repurchase or other acquisition of Indebtedness that is subordinated in right of payment to the Notes or the Subsidiary Guarantees purchased, redeemed, defeased or otherwise acquired in anticipation of satisfying a sinking fund obligation, principal installment or final maturity, in each case due within one year of the date of purchase, repurchase, redemption, defeasance or acquisition, and (c) any payment of principal at the Stated Maturity thereof); or

(4) make any Restricted Investment (all such payments and other actions set forth in these clauses (1) through (4) being collectively referred to as “Restricted Payments”),

unless, at the time of and after giving effect to such Restricted Payment, no Default (except a Reporting Default) or Event of Default has occurred and is continuing or would occur as a consequence of such Restricted Payment and:

(I) the Company would, at the time of such Restricted Payment immediately after giving pro forma effect thereto as if the same had occurred at the beginning of the applicable four-quarter period, be permitted to incur at least $1.00 of additional Indebtedness pursuant to the Fixed Charge Coverage Ratio test set forth in the first paragraph of Section 4.11; and

(II) such Restricted Payment, together with the aggregate amount of all other Restricted Payments made by the Company and its Restricted Subsidiaries (excluding Restricted Payments permitted by clauses (2), (3), (4), (5), (8), (9), (11) and (13) of the next succeeding paragraph) since November 2, 2010, is less than the sum, without duplication, of (the “Restricted Payments Basket”):

(a) 50% of the aggregate Consolidated Net Income of the Company accrued on a cumulative basis during the period beginning on the Measurement Date and ending on the last day of the Company’s last fiscal quarter ending prior to the date of the Restricted Payment (or, if such aggregate cumulative Consolidated Net Income shall be a loss, minus 100% of such loss); plus

(b) 100% of the aggregate net cash proceeds, and the Fair Market Value of any Capital Stock of Persons (other than an Unrestricted Subsidiary) engaged primarily in the Oil and Gas Business or any other assets that are used or useful in the Oil and Gas Business, in each case received by the Company after the Measurement Date as a contribution to its common equity capital or from the issue or sale after the Measurement

Date of Equity Interests of the Company (other than Disqualified Stock) or from the issue or sale after the Measurement Date of convertible or exchangeable Disqualified Stock or convertible or exchangeable debt securities of the Company that have been converted into or exchanged for such Equity Interests (other than Equity Interests (or Disqualified Stock or debt securities) sold to a Subsidiary of the Company) or received upon the exercise of any options, warrants or rights to purchase Equity Interests (other than Disqualified Stock) of the Company; plus

(c) the amount equal to the net reduction in Restricted Investments made by the Company or any of its Restricted Subsidiaries in any Person since the Measurement Date resulting from:

(i) repurchases or redemptions of such Restricted Investments by such Person, proceeds realized upon the sale of such Restricted Investment to a purchaser other than the Company or a Subsidiary of the Company, repayments of loans or advances or other transfers of assets (including by way of interest payments, dividend or distribution) by such Person to the Company or any Restricted Subsidiary of the Company; plus

(ii) the redesignation of Unrestricted Subsidiaries as Restricted Subsidiaries or the merger or consolidation of an Unrestricted Subsidiary with and into the Company or any Restricted Subsidiary (valued in each case as provided in the definition of “Investment”) not to exceed, in the case of any Unrestricted Subsidiary, the amount of Investments previously made by the Company or any Restricted Subsidiary of the Company in such Unrestricted Subsidiary; plus

(iii) an amount equal to any amount included as a Restricted Payment pursuant to clause (II) of the first paragraph of this Section 4.09 on account of any guarantee entered into by the Company or any Restricted Subsidiary; to the extent that such guarantee has not been called upon and the obligation arising under such guarantee no longer exists or has been reduced; plus

(iv) in the event the Company or any Restricted Subsidiary makes any Investment in a Person that, as a result of or in connection with such Investment, becomes a Restricted Subsidiary or is merged or consolidated with the Company or a Restricted Subsidiary, an amount equal to the amount included as a Restricted Payment pursuant to clause (II) of the first paragraph of this Section 4.09 on account of the Company’s or any Restricted Subsidiary’s Investment in such Person prior to the time it became a Restricted Subsidiary or the time of such merger or consolidation; plus

(d) the amount by which Indebtedness of the Company or its Restricted Subsidiaries is reduced on the Company’s balance sheet upon the conversion or exchange (other than by a Subsidiary of the Company) subsequent to the Measurement Date of any Indebtedness of the Company or its Restricted Subsidiaries convertible into or exchangeable for Equity Interests of the Company (other than Disqualified Stock) (less the amount of cash, or the Fair Market Value of any other property, distributed by the Company upon such conversion or exchange),

in each case to the extent such amounts have not been included in Consolidated Net Income for any period commencing on or after the Measurement Date.

(1) the payment of any dividend or distribution or the consummation of an irrevocable redemption within 60 days after the date of its declaration or the giving of notice of such a redemption, if at the date of declaration or notice the payment would have complied with the provisions of this Indenture;

(2) the redemption, repurchase, retirement, defeasance or other acquisition of any subordinated Indebtedness of the Company or any Subsidiary Guarantor or of any Equity Interests of the Company in exchange for, or out of the net cash proceeds of the substantially concurrent (a) contribution (other than from a Restricted Subsidiary of the Company) to the equity capital of the Company or (b) sale (other than to a Restricted Subsidiary of the Company) of, Equity Interests of the Company (other than Disqualified Stock), with a sale being deemed substantially concurrent if such redemption, repurchase, retirement, defeasance or acquisition occurs not more than 120 days after such sale; provided, however, that the amount of any such net cash proceeds that are utilized for any such redemption, repurchase, retirement, defeasance or other acquisition will be excluded or deducted from clause (II) of this Section 4.09;

(3) the defeasance, redemption, repurchase, retirement or other acquisition of subordinated Indebtedness or Disqualified Stock of the Company or any Subsidiary Guarantor with the net cash proceeds from a substantially concurrent incurrence of, or in exchange for, Permitted Refinancing Indebtedness, with an incurrence of Permitted Refinancing Indebtedness being deemed substantially concurrent if such defeasance, redemption, repurchase, retirement or acquisition occurs not more than 120 days after such incurrence;

(4) the payment of any dividend or distribution by a Restricted Subsidiary of the Company to the holders of such Restricted Subsidiary’s Equity Interests on a pro rata basis or on a basis more favorable to the Company or a Restricted Subsidiary;

(5) so long as no Default (other than a Reporting Default) or Event of Default shall have occurred and be continuing or would be caused thereby, the repurchase, redemption or other acquisition or retirement for value (other than for any Equity Interest) of any Equity Interests of the Company or any Restricted Subsidiary of the Company pursuant to any director, employee or consultant equity subscription agreement or equity option agreement or other employee benefit plan or to satisfy obligations under any Equity Interests option plan or similar arrangement other than any rights described under clause 9(b) below; provided, however, that the aggregate price paid for all such repurchased, redeemed, acquired or retired Equity Interests may not exceed $3.0 million in any calendar year (with any portion of such $3.0 million amount that is unused in any calendar year to be carried forward to successive calendar years and added to such amount) plus, to the extent not previously applied or included,

(a) the cash proceeds received by the Company or any of its Restricted Subsidiaries from sales of Equity Interests of the Company to employees, consultants or directors of the Company or its Affiliates that occur after November 2, 2010 (to the extent the cash proceeds from the sale of such Equity Interests have not otherwise been applied to the payment of Restricted Payments by virtue of clause (II)(b) of the first paragraph of this Section 4.09); and

(b) the cash proceeds of key man life insurance policies received by the Company or any of its Restricted Subsidiaries after November 2, 2010;

(6) any purchase, redemption, defeasance, retirement or other acquisition of Indebtedness that is subordinated in right of payment to the Notes or a Subsidiary Guarantee pursuant to the provisions of such Indebtedness in the event of a Change of Control or an Asset Sale, in each case plus accrued and unpaid interest thereon, but only if:

(a) in the case of a Change of Control, the Company has first complied with and fully satisfied its obligations under Section 4.16; or

(b) in the case of an Asset Sale, the Company has complied with and fully satisfied its obligations in accordance with Section 4.12;

(7) the repurchase, redemption or other acquisition for value of Equity Interests of the Company or any Restricted Subsidiary of the Company representing fractional shares of such Equity Interests in connection with a merger or consolidation involving the Company or such Restricted Subsidiary or any other transaction permitted by this Indenture;

(8) the repurchase, redemption or other acquisition of Equity Interests deemed to occur upon the exercise or conversion of stock options, warrants or other convertible securities if such Equity Interests represent a portion of the exercise or conversion price thereof;

(9) the defeasance, repurchase, redemption or other acquisition or retirement for value of (a) any Equity Interests of the Company or any Restricted Subsidiary of the Company held by any current or former officers, directors or employees of the Company or any of its Restricted Subsidiaries in connection with the exercise or vesting of any equity compensation (including, without limitation, stock options, restricted stock and phantom stock) in order to satisfy any tax withholding obligation with respect to such exercise or vesting or (b) to the extent otherwise constituting a Restricted Payment, any rights under any cash or equity-settled equity stock appreciation agreement or plan of the Company or any Restricted Subsidiary;

(10) any payments in connection with a consolidation, merger or transfer of assets in connection with a transaction that is not prohibited by this Indenture not to exceed $25.0 million in the aggregate after the Initial Issuance Date;

(11) the payment of any dividends or distributions by the Company to the holders of its Disqualified Stock or preferred stock; provided that such Disqualified Stock or preferred stock is issued on or after the Initial Issuance Date in accordance with the first paragraph of Section 4.11;

(12) the declaration and payment of distributions effecting “poison pill” rights plans provided that any securities or rights so distributed have a nominal Fair Market Value at the time of declaration;

(13) (i) cash capital contributions to, and funding expenses for the benefit of, foreign Unrestricted Subsidiaries or foreign Joint Ventures in an amount not to exceed $50.0 million in the aggregate since November 2, 2010, and (ii) guarantees to fund any such expenditures; or

(14) so long as no Default (other than a Reporting Default) or Event of Default shall have occurred and be continuing or would be caused thereby, other Restricted Payments in an aggregate amount not to exceed $25.0 million at any time outstanding since November 2, 2010 (after giving effect to any dividends, interest payments, return of capital and subsequent reduction in the amount of any Investments made pursuant to this clause as a result of the repayment or other disposition thereof, in an amount not to exceed the amount of such Investments previously made pursuant to this clause); provided, however, that if any Investment pursuant to this clause (14) is made in any Person that is not a Restricted Subsidiary of the Company at the date of the making of such Investment and such Person becomes a Restricted Subsidiary of the Company after such date, such Investment shall thereafter be deemed to have been made pursuant to clause (1) of the definition of “Permitted Investments” and shall cease to have been made pursuant to this clause (14) for so long as such Person continues to be a Restricted Subsidiary.

The amount of all Restricted Payments (other than cash) will be the Fair Market Value on the date of the Restricted Payment of the asset(s) or securities proposed to be transferred or issued by the Company or any of its Restricted Subsidiaries, as the case may be, pursuant to the Restricted Payment. The Fair Market Value of any assets or securities that are required to be valued by this Section 4.09 will be determined, in the case of amounts under $20.0 million, by an officer of the Company and, in the case of amounts over $20.0 million, by the Board of Directors of the Company, whose determination shall be evidenced by a Board Resolution. For purposes of determining compliance with this Section 4.09, in the

event that a Restricted Payment meets the criteria of more than one of the categories of Restricted Payments described in the preceding clauses (1) — (14) or pursuant to the Restricted Payments Basket or as a Permitted Investment, the Company will be permitted to divide or classify (or later divide, classify or reclassify in whole or in part in its sole discretion) such Restricted Payment in any manner that complies with this Section 4.09.

The Company will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly, create or permit to exist or become effective any consensual encumbrance or restriction on the ability of any Restricted Subsidiary of the Company to:

(1) pay dividends or make any other distributions on its Capital Stock to the Company or any of its Restricted Subsidiaries, or pay any Indebtedness or other obligations owed to the Company or any of its Restricted Subsidiaries;

(2) make loans or advances to the Company or any of its Restricted Subsidiaries; or

(3) sell, lease or transfer any of its assets to the Company or any of its Restricted Subsidiaries.

However, the preceding restrictions of this Section 4.10 will not apply to encumbrances or restrictions existing under or by reason of:

(1) agreements (including in respect of any Credit Facilities) as in effect on the Initial Issuance Date and any amendments, modifications, restatements, renewals, increases, supplements, refundings, replacements or refinancings of those agreements (or the agreements referred to in this clause (1)) or the Indebtedness to which those agreements (or the agreements referred to in this clause (1)) relate, provided that the amendments, modifications, restatements, renewals, increases, supplements, refundings, replacements or refinancings are no more restrictive, taken as a whole, with respect to such dividend, distribution and other payment restrictions than those contained in those agreements on the Initial Issuance Date, as determined by the Board of Directors of the Company in its reasonable and good faith judgment;

(4) any agreement or instrument with respect to a Restricted Subsidiary that is not a Restricted Subsidiary of the Company on the Initial Issuance Date, in existence at the time such Person becomes a Restricted Subsidiary of the Company and not incurred in connection with, or in contemplation of, such Person becoming a Restricted Subsidiary; provided that such encumbrances and restrictions are not applicable to the Company or any Restricted Subsidiary or the assets of the Company or any Restricted Subsidiary other than such Subsidiary which is becoming a Restricted Subsidiary;

(5) any agreement or instrument governing any Permitted Acquisition Indebtedness, so long as such agreement or instrument (A) was not entered into in contemplation of the acquisition, merger or consolidation transaction related thereto, and (B) is not applicable to any Person, or the assets of any Person, other than the Person, or the assets or Subsidiaries of the Person, subject to such acquisition, merger or consolidation, so long as the agreement containing such restriction does not violate any other provision of the Indenture;

(6) instruments governing Indebtedness of the Company or any of the Subsidiary Guarantors permitted to be incurred pursuant to an agreement entered into subsequent to the Initial Issuance Date in accordance with Section 4.11; provided that the provisions relating to such encumbrance or restriction

contained in such instruments are not materially more restrictive, taken as a whole, than the provisions contained in the Credit Agreement and in the this Indenture as in effect on the Initial Issuance Date, as determined by the Board of Directors of the Company in its reasonable and good faith judgment;

(7) (i) customary non-assignment provisions in Hydrocarbon purchase and sale or exchange agreements, joint operating agreements, or similar operational agreements or in licenses or leases, or (ii) other encumbrances or restrictions in agreements or instruments relating to specific assets or property that restrict generally the transfers of such assets or property, provided, however, that such other encumbrances or restrictions do not materially impair the ability of the Company to make scheduled payments on the Notes when due in each case entered into in the ordinary course of business or customary in the Oil and Gas Business;

(8) Capital Lease Obligations, mortgage financings or purchase money obligations, in each case for property acquired in the ordinary course of business or which is customary in the Oil and Gas Business that impose restrictions on that property purchased or leased of the nature described in clause (3) of the preceding paragraph;

(9) any agreement for the sale or other disposition of a Restricted Subsidiary of the Company that restricts distributions by that Restricted Subsidiary pending its sale or other disposition;

(10) Permitted Refinancing Indebtedness, provided that the restrictions contained in the agreements governing such Permitted Refinancing Indebtedness are not materially more restrictive, taken as a whole, than those contained in the agreements governing the Indebtedness being refinanced, as determined by the Board of Directors of the Company in its reasonable and good faith judgment;

(11) Liens securing Indebtedness otherwise permitted to be incurred under the provisions of Section 4.14 that limit the right of the debtor to dispose of the assets subject to such Liens;

(12) provisions limiting the disposition or distribution of assets or property in joint venture agreements, asset sale agreements, stock sale agreements and other similar agreements entered into (a) in the ordinary course of business or which are customary in the Oil and Gas Business, or (b) with the approval of the Company’s Board of Directors, which limitations are applicable only to the assets that are the subject of such agreements;

(13) any agreement or instrument relating to any property or assets acquired after the Initial Issuance Date, so long as such encumbrance or restriction relates only to the assets so acquired and is not and was not created in anticipation of such acquisition;

(14) restrictions on cash, Cash Equivalents or other deposits or net worth imposed by customers or lessors under contracts or leases entered into in the ordinary course of business or which are customary in the Oil and Gas Business;

(15) customary encumbrances and restrictions contained in agreements of the types described in the definition of “Permitted Business Investments”;

(17) the issuance of preferred securities by a Restricted Subsidiary of the Company or the payment of dividends thereon in accordance with the terms thereof; provided that issuance of such preferred securities is permitted pursuant to Section 4.11 and the terms of such preferred securities do not expressly restrict the ability of a Restricted Subsidiary of the Company to pay dividends or make any other distributions on its Equity Interests (other than requirements to pay dividends or liquidation preferences on such preferred securities prior to paying any dividends or making any other distributions on such other Equity Interests);

(19) restrictions on repayment of Indebtedness and other obligations to, and restrictions on the making of loans, advances, sales, leases and transfers to, a Restricted Subsidiary that does not directly or indirectly own Capital Stock of the obligor, lender, seller, lessor or transferor, as the case may be.

The Company will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly, create, incur, issue, assume, guarantee or otherwise become directly or indirectly liable, contingently or otherwise, with respect to (collectively, “incur”) any Indebtedness, the Company will not issue any Disqualified Stock, and the Company will not permit any of its Restricted Subsidiaries to issue any Disqualified Stock or preferred securities; provided, however, that the Company and any of the Subsidiary Guarantors may incur Indebtedness and the Company may issue Disqualified Stock and any Subsidiary Guarantor may issue Disqualified Stock or preferred securities, if the Fixed Charge Coverage Ratio for the Company’s most recently ended four full fiscal quarters for which internal financial statements are available immediately preceding the date on which such additional Indebtedness is incurred or such preferred securities or Disqualified Stock is or are issued, as the case may be, would have been at least 2.50 to 1.0, determined on a pro forma basis (including a pro forma application of the net proceeds therefrom), as if the additional Indebtedness had been incurred or such preferred securities or Disqualified Stock had been issued, as the case may be, at the beginning of such four-quarter period.

The first paragraph of this Section 4.11 will not prohibit the incurrence of any of the following items of Indebtedness or the issuance of any Disqualified Stock or any preferred securities described below (collectively, “Permitted Debt”):

(1) the incurrence by the Company or any of the Subsidiary Guarantors of additional Indebtedness (including letters of credit) under one or more Credit Facilities, provided that, after giving effect to any such incurrence, the aggregate principal amount of all Indebtedness outstanding under the Company’s and its Restricted Subsidiaries’ Credit Facilities incurred under this clause (1) (with letters of credit being deemed to have a principal amount equal to the maximum potential liability of the Company and its Subsidiaries thereunder) does not exceed the greater of (a) $600.0 million and (b) an amount equal to the sum of $250.0 million plus 35.0% of the Company’s Adjusted Consolidated Net Tangible Assets determined as of the date of such incurrence;

(2) the incurrence by the Company or its Restricted Subsidiaries of the Existing Indebtedness not otherwise referred to in this definition of “Permitted Debt”;

(3) the incurrence by the Company and the Subsidiary Guarantors of Indebtedness represented by the Notes (excluding any Additional Notes) and the related Subsidiary Guarantees;

(4) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness represented by Capital Lease Obligations, mortgage financings or purchase money obligations, in each case incurred for the purpose of financing all or any part of the purchase price or cost of design, installation, repair, replacement, construction or improvement of property, plant or equipment used in the business of the Company or such Restricted Subsidiary (whether through the direct purchase of such assets or the Capital Stock of any Person owning such assets (but no other material assets)) and related financing costs, and Attributable Debt in respect of Sale Leaseback Transactions, including all Permitted Refinancing Indebtedness incurred to extend, refinance, renew, replace, defease or refund any Indebtedness incurred pursuant to this clause (4), provided that after giving effect to any such incurrence, the aggregate principal amount of all Indebtedness incurred pursuant to this clause (4) and then outstanding does not exceed the greater of (a) $25.0 million and (b) 2.5% of the Company’s Adjusted Consolidated Net Tangible Assets determined as of the date of such incurrence;

(5) the incurrence or issuance by the Company or any of its Restricted Subsidiaries of Permitted Refinancing Indebtedness in exchange for, or the net proceeds of which shall be used to extend, refinance, renew, replace, defease, discharge, refund or otherwise retire for value, in whole or in part, Indebtedness of the Company or any of its Restricted Subsidiaries (other than intercompany Indebtedness) or Disqualified Stock of the Company, in each case that was permitted by this Indenture to be incurred pursuant to the first paragraph of this Section 4.11 or clauses (2), (3), (4), (5) and (12) of this paragraph;

(6) the incurrence by the Company or any of its Restricted Subsidiaries of intercompany Indebtedness between or among any of the Company and any of its Restricted Subsidiaries; provided, however, that:

(a) if the Company is the obligor on such Indebtedness and a Subsidiary Guarantor is not the obligee, such Indebtedness must be expressly subordinated to the prior payment in full in cash of all Obligations with respect to the Notes, or if a Subsidiary Guarantor is the obligor on such Indebtedness and neither the Company nor another Subsidiary Guarantor is the obligee, such Indebtedness must be expressly subordinated to the prior payment in full in cash of all Obligations with respect to the Subsidiary Guarantee of such Subsidiary Guarantor; and

(b) (i) any subsequent issuance or transfer of Equity Interests that results in any such Indebtedness being held by a Person other than the Company or a Restricted Subsidiary of the Company and (ii) any sale or other transfer of any such Indebtedness to a Person that is neither the Company nor a Restricted Subsidiary of the Company will be deemed, in each case, to constitute an incurrence (as of the date of such issuance, sale or transfer) of such Indebtedness by the Company or such Restricted Subsidiary, as the case may be, that was not permitted by this clause (6);

(7) the incurrence by the Company or any of its Restricted Subsidiaries of obligations under Hedging Contracts;

(8) the guarantee by the Company or any of its Restricted Subsidiaries of Indebtedness of the Company or any of its Restricted Subsidiaries that was permitted to be incurred by another provision of this Section 4.11;

(9) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness relating to net gas balancing positions arising in the ordinary course of business and consistent with past practice;

(10) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness in respect of bid, performance, surety and similar bonds issued for the account of the Company and any of its Restricted Subsidiaries in the ordinary course of business or which are customary in the Oil and Gas Business, including guarantees and obligations of the Company or any of its Restricted Subsidiaries with respect to letters of credit supporting such obligations (in each case other than an obligation for money borrowed);

(11) the issuance by any of the Company’s Restricted Subsidiaries to the Company or to any of its Restricted Subsidiaries of any preferred securities; provided, however, that:

(a) any subsequent issuance or transfer of Equity Interests that results in any such preferred securities being held by a Person other than the Company or a Restricted Subsidiary of the Company; and

(b) any sale or other transfer of any such preferred securities to a Person that is not either the Company or a Restricted Subsidiary of the Company shall be deemed, in each case, to constitute an issuance (as of the date of such issuance, sale or transfer) of such preferred securities by such Restricted Subsidiary that was not permitted by this clause (11);

(13) the incurrence by the Company or its Restricted Subsidiaries of Indebtedness arising from the honoring by a bank or other financial institution of a check, draft or similar instrument inadvertently drawn against insufficient funds in the ordinary course of business;

(14) the incurrence by the Company or its Restricted Subsidiaries of Indebtedness consisting of the financing of insurance premiums in customary amounts consistent with the operations and business of the Company and its Restricted Subsidiaries;

(15) accounts payable or other obligations of the Company or any of its Restricted Subsidiaries to trade creditors created or assumed by the Company or such Restricted Subsidiary in the ordinary course of business or which is customary in the Oil and Gas Business in connection with the obtaining of goods or services;

(16) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness arising from agreements of the Company or any Restricted Subsidiary of the Company providing for indemnification, adjustment of purchase price, earn outs, or similar obligations, in each case, incurred or assumed in connection with the disposition or acquisition of any business, assets or Capital Stock of a Subsidiary in a transaction permitted by this Indenture, other than guarantees of Indebtedness incurred or assumed by any Person acquiring all or any portion of such business, assets or Subsidiary for the purpose of financing such acquisition;

(18) the incurrence by the Company or any of its Restricted Subsidiaries of additional Indebtedness or the issuance by the Company of additional Disqualified Stock or the issuance by any Restricted Subsidiary of preferred securities, provided that, after giving effect to any such incurrence or issuance, the aggregate principal amount of all Indebtedness, Disqualified Stock and preferred securities incurred or issued under this clause (18) and then outstanding does not exceed the greater of (a) $25.0 million and (b) 2.5% of the Company’s Adjusted Consolidated Net Tangible Assets determined as of the date of such incurrence or issuance; and

(19) Indebtedness of the Company or any Restricted Subsidiary to the extent the proceeds are deposited for the purpose of defeasing the Notes pursuant to Section 8.01.

For purposes of determining compliance with this Section 4.11, in the event that an item of Indebtedness or Disqualified Stock or preferred securities meets the criteria of more than one of the categories of Permitted Debt described in clauses (1) through (19) above, or is entitled to be incurred or issued pursuant to the first paragraph of this Section 4.11, the Company will be permitted to divide and classify (or later classify, reclassify or re-divide in whole or in part in its sole discretion) such item of Indebtedness or Disqualified Stock or preferred securities in any manner that complies with this Section 4.11, provided that any Indebtedness under the Credit Agreement that was incurred on or prior to, and outstanding on the Initial Issuance Date shall be deemed to have been initially incurred on the Initial Issuance Date pursuant to clause (1) of the definition of “Permitted Debt” rather than the first paragraph of this Section 4.11. For purposes of determining any particular amount of Indebtedness under this covenant, (i) guarantees of, or obligations in respect of letters of credit relating to, Indebtedness otherwise included in the determination of such amount shall not also be included except to the extent that such Indebtedness exceeds such guarantee or letter of credit and (ii) if obligations in respect of letters of credit are incurred pursuant to a Credit Facility and are being treated as incurred pursuant to clause (1) of the definition of “Permitted Debt” and the letters of credit relate to other Indebtedness, then such other Indebtedness shall not be included except to the extent that the amount of such Indebtedness exceeds the amount of such letters of credit.

The accrual of interest, the accrual of dividends, the accretion or amortization of original issue discount, the payment of interest on any Indebtedness in the form of additional Indebtedness, and the payment of dividends on Disqualified Stock or preferred securities in the form of additional shares of Disqualified Stock or preferred securities will not be deemed to be an incurrence of Indebtedness or an issuance of Disqualified Stock or preferred securities for purposes of this Section 4.11, provided, in each such case, that the amount thereof is included in Fixed Charges of the Company as accrued.

For purposes of determining compliance with any U.S. dollar-denominated restriction on the incurrence of Indebtedness, the U.S. dollar-equivalent principal amount of Indebtedness denominated in a foreign currency will be calculated based on the relevant currency exchange rate in effect on the date the Indebtedness was incurred, in the case of term Indebtedness, or first committed, in the case of revolving credit Indebtedness; provided that if such Indebtedness is incurred to refinance other Indebtedness denominated in a foreign currency, and the refinancing would cause the applicable U.S. dollar-dominated restriction to be exceeded if calculated at the relevant currency exchange rate in effect on the date of the refinancing, such U.S. dollar-dominated restriction shall be deemed not to have been exceeded so long as the principal amount of such refinancing Indebtedness does not exceed the principal amount of such Indebtedness being refinanced (plus all accrued and unpaid interest on such Indebtedness, and the amount of all fees, expenses and premiums incurred in connection therewith). Notwithstanding any other provision of this Section 4.11, the maximum amount of Indebtedness that the Company or any Restricted Subsidiary may incur pursuant to this Section 4.11 shall not be deemed to be exceeded solely as a result of fluctuations in the exchange rate of currencies. The principal amount of any Indebtedness incurred to refinance other Indebtedness, if incurred in a different currency from the Indebtedness being refinanced, will be calculated based on the currency exchange rate applicable to the currencies in which the refinancing Indebtedness is denominated that is in effect on the date of such refinancing.

The Company will not, and will not permit any of its Restricted Subsidiaries to, consummate an Asset Sale unless:

(1) the Company (or the Restricted Subsidiary, as the case may be) receives consideration (including by way of relief from, or any Person assuming responsibilities for, any liabilities, contingent or otherwise), as determined (on the date of contractually agreeing to such Asset Sale) in good faith by senior management of the Company or, if the consideration with respect to such Asset Sale exceeds $25 million, the Board of Directors of the Company, at least equal to the Fair Market Value of the assets or Equity Interest issued or sold or otherwise disposed of; and

(2) at least 75% of the aggregate consideration to be received by the Company and its Restricted Subsidiaries in such Asset Sale (determined on the date of contractually agreeing to such Asset Sale) and all other Asset Sales since the Initial Issuance Date, on a cumulative basis, is in the form of cash or Cash Equivalents. For purposes of this provision, each of the following will be deemed to be cash:

(a) any liabilities, as shown on the Company’s or such Restricted Subsidiary’s most recent balance sheet, of the Company or any Restricted Subsidiary (other than contingent liabilities and liabilities that are by their terms subordinated in right of payment to the Notes or any Subsidiary Guarantee) that are assumed by the transferee of any such assets pursuant to a customary novation agreement that releases the Company or such Restricted Subsidiary from further liability;

(b) any securities, notes or other obligations received by the Company or any such Restricted Subsidiary from such transferee that are, within 180 days after the Asset Sale, converted by the Company or such Subsidiary into cash or Cash Equivalents, to the extent of the cash received in that conversion;

(c) accounts receivable of a business retained by the Company or any of its Restricted Subsidiaries, as the case may be, following the sale of such business, provided that such accounts receivable (i) are not past due more than 90 days and (ii) do not have a payment date greater than 120 days from the date of the invoices creating such accounts receivable; and

(d) solely in the case of any Asset Sale of Production Facility or Pipeline Assets, the Company or the Restricted Subsidiary receives Permitted MLP Securities;

provided that in the case of any Asset Sale pursuant to a condemnation, appropriation or similar taking, including by deed in lieu of condemnation, such Asset Sale shall not be required to satisfy the requirements of items (1) and (2) above. Notwithstanding the preceding, the 75% limitation referred to above shall be deemed satisfied with respect to any Asset Sale in which the cash or Cash Equivalents portion of the consideration received therefrom, determined in accordance with the preceding provision on an after-tax basis, is equal to or greater than what the after-tax proceeds would have been had such Asset Sale complied with the aforementioned 75% limitation.

Within 365 days after the receipt of any Net Proceeds from an Asset Sale, the Company (or the applicable Restricted Subsidiary, as the case may be) may apply those Net Proceeds at its option to any combination of the following:

(3) to make capital expenditures in respect of the Company’s or its Restricted Subsidiaries’ Oil and Gas Business.

The requirement of clause (2) or (3) of the preceding paragraph shall be deemed to be satisfied if a bona fide binding contract committing to make the investment, acquisition or expenditure referred to therein is entered into by the Company or any of its Restricted Subsidiaries with a Person other than an Affiliate of the Company within the time period specified in the preceding paragraph and such Net Proceeds are subsequently applied in accordance with such contract within six months following the date such agreement is entered into.

Pending the final application of any Net Proceeds, the Company or any Restricted Subsidiary of the Company may invest the Net Proceeds in any manner that is not prohibited by this Indenture. Any Net Proceeds from Asset Sales that are not applied or invested as provided in the preceding paragraph will constitute “Excess Proceeds.”

On the 366^th day after an Asset Sale (or, at the Company’s option, any earlier date), if the aggregate amount of Excess Proceeds then exceeds $20.0 million, the Company will make an Asset Sale Offer to all Holders of Notes, and to all holders of Pari Passu Indebtedness then outstanding, to purchase the maximum principal amount of Notes and such Pari Passu Indebtedness that may be purchased out of the Excess Proceeds. The offer price in any Asset Sale Offer will be equal to 100% of principal amount plus accrued and unpaid interest, if any, thereon to the Settlement Date, subject to the right of Holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the Settlement Date, and will be payable in cash. If any Excess Proceeds remain after consummation of an Asset Sale Offer, the Company may use those Excess Proceeds for any purpose not otherwise prohibited by this Indenture. If the aggregate principal amount of Notes and Pari Passu Indebtedness tendered into such Asset Sale Offer exceeds the amount of Excess Proceeds, the Trustee will select the Notes and such Pari Passu Indebtedness to be purchased on a pro rata basis (with such adjustments as may be deemed appropriate by the Trustee so that only Notes in denominations of $2,000, or integral multiples of $1,000 in excess of $2,000, shall be purchased). Upon surrender of a Note that is repurchased in part, the Company shall issue in the name of the applicable Holder and the Trustee shall authenticate for such Holder at the expense of the Company a Note equal in principal amount to the non-repurchased portion of the Note surrendered. Upon completion of each Asset Sale Offer, the amount of Excess Proceeds will be reset at zero.

The Company will comply with the requirements of Rule 14e-1 under the Exchange Act and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with each repurchase of Notes pursuant to an Asset Sale Offer. To the extent that the provisions of any securities laws or regulations conflict with the provisions of this Section 4.12, the Company will comply with the applicable securities laws and regulations and will not be deemed to have breached its obligations under such provisions by virtue of such compliance.

Prior to complying with the Asset Sale Offer provisions of this Section 4.12, but in any event no later than the date of the Asset Sale Offer, the Company or any Subsidiary Guarantor must either repay all of its other outstanding Senior Debt or obtain the requisite consents, if any, under all agreements governing such Senior Debt to permit the repurchase of Notes required by the provisions of this Section 4.12.

For purposes of this Section 4.12, references to the application of Net Proceeds include the application or investment of cash in an amount equal to such Net Proceeds.

The Company will not, and will not permit any of its Restricted Subsidiaries to, make any payment to, or sell, lease, transfer or otherwise dispose of any of its assets to, or purchase any assets from, or enter into or make or amend any transaction, contract, agreement, understanding, loan, advance or guarantee with, or for the benefit of, any Affiliate of the Company (each, an “Affiliate Transaction”), unless:

(1) the Affiliate Transaction is on terms that are not materially less favorable to the Company or the relevant Restricted Subsidiary than those that would have been obtained in a comparable transaction by the Company or such Restricted Subsidiary with an unrelated Person or, if in the good faith judgment of the Company’s Board of Directors, no comparable transaction is available with which to compare such Affiliate Transaction, such Affiliate Transaction is otherwise fair to the Company or the relevant Restricted Subsidiary from a financial point of view; and

(a) with respect to any Affiliate Transaction or series of related Affiliate Transactions involving aggregate consideration to or from an Affiliate in excess of $15.0 million, an Officers’ Certificate certifying that such Affiliate Transaction complies with this Section 4.13; and

(b) with respect to any Affiliate Transaction or series of related Affiliate Transactions involving aggregate consideration to or from an Affiliate in excess of $25.0 million, a resolution of the Board of Directors of the Company set forth in an Officers’ Certificate certifying that such Affiliate Transaction complies with this Section 4.13 and that such Affiliate Transaction has been approved by a majority of the disinterested members of the Board of Directors of the Company.

The following items will not be deemed to be Affiliate Transactions and, therefore, will not be subject to the provisions of the prior paragraph of this Section 4.13:

(1) any employment agreement or arrangement, equity award, equity option or cash or equity settled equity appreciation agreement or plan, employee benefit plan, officer or director indemnification agreement, severance agreement, consulting agreement or other compensation plan or arrangement entered into by the Company or any of its Restricted Subsidiaries in the ordinary course of business or which is customary in the Oil and Gas Business, and payments, awards, grants or issuances of securities pursuant thereto;

(2) transactions between or among any of the Company and its Restricted Subsidiaries (or any entity that becomes a Restricted Subsidiary as a result of such transaction);

(3) transactions with a Person (other than an Unrestricted Subsidiary of the Company) that is an Affiliate of the Company solely because the Company owns, directly or indirectly, an Equity Interest in, or otherwise controls, such Person or has nominated or appointed a person to the Board of Directors of that Person;

(4) customary compensation, indemnification and other benefits made available to officers, directors, employees or consultants of the Company or a Restricted Subsidiary or Affiliate of the Company, including reimbursement or advancement of out-of-pocket expenses and provisions of officers’ and directors’ liability insurance;

(5) sales of Equity Interests (other than Disqualified Stock) to, or receipt of capital contributions from, Affiliates of the Company and any dividend or distribution payable in Equity Interests (other than Disqualified Stock);

(6) any Permitted Investments or Restricted Payments that are permitted by Section 4.09 (or a transaction that would constitute a Restricted Payment but for an exclusion from the definition thereof);

(7) transactions between the Company or any of its Restricted Subsidiaries and any Person that would not otherwise constitute an Affiliate Transaction except for the fact that one director of such other Person is also a director of the Company or such Restricted Subsidiary, as applicable; provided that such director abstains from voting as a director of the Company or such Restricted Subsidiary, as applicable, on any matter involving such other Person;

(8) the existence of, and the performance of obligations of the Company or any of its Restricted Subsidiaries under the terms of, any written agreement to which the Company or any of its Restricted Subsidiaries is a party on the Initial Issuance Date, as such agreements may be amended, modified, supplemented or replaced from time to time; provided, however, that any amendment, modification, supplement or replacement entered into after the Initial Issuance Date will be permitted to the extent that its terms are not materially more disadvantageous, taken as a whole, to the Holders of the Notes than the terms of the agreements in effect on the Initial Issuance Date (as conclusively evidenced by a Board Resolution);

(9) any transaction in which the Company or any of its Restricted Subsidiaries, as the case may be, delivers to the Trustee an opinion from an accounting, appraisal or investment banking firm of national standing stating that such transaction is fair to the Company or such Restricted Subsidiary from a financial point of view or that such transaction meets the requirements of clause (1) of the first paragraph of this Section 4.13;

(10) (a) guarantees by the Company or any of its Restricted Subsidiaries of performance of obligations of the Company’s Unrestricted Subsidiaries in the ordinary course of business or which is customary in the Oil and Gas Business, and (b) pledges by the Company or any Restricted Subsidiary of the Company of Equity Interests in Unrestricted Subsidiaries for the benefit of lenders or other creditors of the Company’s Unrestricted Subsidiaries;

(11) any Affiliate Transaction with a Person in its capacity as a holder of Indebtedness or Capital Stock of the Company or any Restricted Subsidiary of the Company if such Person is treated no more favorably than the other holders of Indebtedness or Capital Stock of the Company or such Restricted Subsidiary;

(12) transactions with joint venture partners, customers, clients, suppliers or purchasers or sellers of goods or services, or lessors or lessees of property, in each case in the ordinary course of business or which is customary in the Oil and Gas Business and otherwise in compliance with the terms of this

Indenture similar to those contained in similar contracts entered into by the Company or any Restricted Subsidiary and third parties, or if neither the Company nor any Restricted Subsidiary has entered into a similar contract with a third party, which are, in the aggregate (taking into account all the costs and benefits associated with such transactions), not materially less favorable to the Company and its Restricted Subsidiaries than those that would have been obtained in a comparable transaction by the Company or such Restricted Subsidiary with an unrelated Person, in the good faith determination of the Company’s Board of Directors or any executive officer of the Company involved in or otherwise familiar with such transaction;

(13) transactions entered into by a Person prior to the time such Person becomes a Subsidiary of the Company or is merged or consolidated into the Company or a Subsidiary of the Company (provided such transaction is not entered into in contemplation of such event);

(14) dividends and distributions to the Company and its Restricted Subsidiaries by any Unrestricted Subsidiary or Joint Venture; and

(15) transactions with Avista or any of its Subsidiaries entered into in connection with the Avista Joint Venture; provided such transactions are on terms that are not materially less favorable, taken as a whole, to the Company or the relevant Restricted Subsidiary than those that would have been obtained in a comparable transaction by the Company or such Restricted Subsidiary with an unrelated Person.

The Company will not, and will not permit any of its Restricted Subsidiaries to, create, incur, assume or otherwise cause or suffer to exist or become effective any Lien of any kind (other than Permitted Liens) upon any of its assets (whether now owned or hereafter acquired), securing Indebtedness, unless the Notes or the Subsidiary Guarantee of such Restricted Subsidiary, as applicable, is secured on an equal and ratable basis with (or, in the case of obligations subordinated in right of payment to the Notes or such Subsidiary Guarantee, as the case may be, on a basis senior (to at least the same extent as the Notes are senior in right of payment) to) the obligations so secured until such time as such obligations are no longer secured by a Lien.

Any Lien on any assets of the Company or any of its Restricted Subsidiaries created for the benefit of the Holders of the Notes pursuant to the preceding paragraph shall provide by its terms that such Lien shall be automatically and unconditionally released and discharged at such time as there are no other Liens of any kind (other than Permitted Liens) on such assets securing Indebtedness.

If, after the Initial Issuance Date, any Restricted Subsidiary of the Company that is not already a Subsidiary Guarantor guarantees any other Indebtedness of the Company or any Indebtedness of any Restricted Subsidiary in excess of the De Minimis Guaranteed Amount, or any Restricted Subsidiary, if not then a Subsidiary Guarantor, incurs any Indebtedness under any of the Credit Facilities, then in either case that Subsidiary shall become a Subsidiary Guarantor by executing a supplemental indenture substantially in the form of Annex B hereto and delivering it to the Trustee within 90 days of the date on which it guaranteed or incurred such Indebtedness, as the case may be, together with any Officers’ Certificate or Opinion of Counsel required by Section 9.06. Notwithstanding the preceding, any Subsidiary Guarantee of a Restricted Subsidiary that was incurred pursuant to this Section 4.15 shall provide by its terms that it shall be automatically and unconditionally released at such time as such Subsidiary Guarantor ceases both (x) to guarantee any other Indebtedness of the Company and any Indebtedness of any other Restricted Subsidiary and (y) to be an obligor with respect to any Indebtedness under any Credit Facility.

Within 30 days following the occurrence of a Change of Control, the Company shall make an offer (a “Change of Control Offer”) to repurchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess of $2,000) of each Holder’s Notes at a purchase price (the “Change of Control Payment”) in cash equal to 101% of the aggregate principal amount of Notes repurchased, plus accrued and unpaid interest, if any, thereon to the date of settlement (the “Change of Control Settlement Date”), subject to the right of Holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the Change of Control Settlement Date. Within 30 days following a Change of Control, the Company shall provide a notice of the Change of Control Offer to each Holder and the Trustee describing the transaction or transactions that constitute the Change of Control and stating:

(a) that the Change of Control Offer is being made pursuant to this Section 4.16 and that all Notes validly tendered and not withdrawn pursuant to the Change of Control Offer will be accepted for payment;

(b) the purchase price and the purchase date, which shall be no earlier than 30 days and no later than 60 days from the date such notice is provided (the “Change of Control Purchase Date”);

(c) that the Change of Control Offer will expire as of the time specified in such notice on the Change of Control Purchase Date and that the Company shall pay the Change of Control Purchase Price for all Notes purchased as of the Change of Control Purchase Date promptly thereafter on the Change of Control Settlement Date;

(e) that, unless the Company defaults in the payment of the Change of Control Payment, all Notes accepted for payment pursuant to the Change of Control Offer shall cease to accrue interest after the Change of Control Settlement Date;

(f) that Holders electing to have any Notes purchased pursuant to a Change of Control Offer will be required to surrender the Notes, properly endorsed for transfer, together with the form entitled “Option of Holder to Elect Purchase” on the reverse of the Notes completed and such customary documents as the Company may reasonably request, to the Paying Agent at the address specified in the notice prior to the termination of the Change of Control Offer on the Change of Control Purchase Date;

(g) that Holders will be entitled to withdraw their election if the Paying Agent receives, prior to the termination of the Change of Control Offer, a telegram, facsimile transmission or letter setting forth the name of the Holder, the principal amount of Notes delivered for purchase, and a statement that such Holder is withdrawing its election to have the Notes purchased; and

(h) that Holders whose Notes are being purchased only in part will be issued Notes equal in principal amount to the unpurchased portion of the Notes surrendered, which unpurchased portion must be equal to $2,000 in principal amount or an integral multiple of $1,000 in excess of $2,000.

If any of the Notes subject to a Change of Control Offer is in the form of a Global Note, then the Company shall modify such notice to the extent necessary to accord with the procedures of the Depositary applicable to repurchases. Further, the Company shall comply with the requirements of Rule 14e-1 under the Exchange Act and any other securities laws and regulations thereunder to the extent such laws and regulations are applicable in connection with the repurchase of Notes as a result of a Change of Control. To the extent that the provisions of any securities laws or regulations conflict with the provisions of this Section 4.16, the Company will comply with the applicable securities laws and regulations and will not be deemed to have breached its obligations under such provisions by virtue of such compliance.

On the Change of Control Purchase Date, the Company shall, to the extent lawful, accept for payment all Notes or portions thereof (in integral multiples of $1,000) properly tendered pursuant to the Change of Control Offer. Promptly thereafter on the Change of Control Settlement Date, the Company shall:

(i) deposit with the Paying Agent by 11:00 a.m., New York City time, an amount equal to the Change of Control Payment in respect of all Notes or portions thereof so tendered; and

(ii) deliver or cause to be delivered to the Trustee the Notes so accepted together with an Officers’ Certificate stating the aggregate principal amount of Notes or portions of Notes being purchased by the Company.

On the Change of Control Settlement Date, the Paying Agent shall mail to each Holder of Notes properly tendered the Change of Control Payment for such Notes (or, if all the Notes are then in global form, make such payment through the facilities of the Depositary) and the Trustee shall authenticate and mail (or cause to be transferred by book entry) to each Holder a new Note equal in principal amount to any unpurchased portion of the Notes surrendered, if any; provided, however, that each such Note will be in a principal amount of $2,000 or an integral multiple of $1,000 in excess of $2,000. The Company shall publicly announce the results of the Change of Control Offer on or as soon as practicable after the Change of Control Settlement Date.

Prior to complying with any of the provisions of this Section 4.16, but in any event no later than the Change of Control Purchase Date, the Company or any Subsidiary Guarantor shall either repay all of its other outstanding Senior Debt or obtain the requisite consents, if any, under all agreements governing such Senior Debt to permit the repurchase of Notes required by this Section 4.16.

The Company shall not be required to make a Change of Control Offer following a Change of Control if (1) a third party makes the Change of Control Offer in the manner, at the time and otherwise in compliance with the requirements set forth in this Indenture applicable to a Change of Control Offer made by the Company and purchases all Notes properly tendered and not withdrawn under such Change of Control Offer or (2) notice of redemption of all Notes has been given pursuant to Section 3.12 unless there is a default in payment of the applicable Redemption Price.

A Change of Control Offer may be made in advance of a Change of Control, and conditioned upon the occurrence of such Change of Control.

In the event that Holders of not less than 90% of the aggregate principal amount of the Outstanding Notes accept a Change of Control Offer and the Company purchases all of the Notes held by such Holders, the Company will have the right, upon not less than 30 nor more than 60 days’ prior notice, given not more than 30 days following the purchase pursuant to such Change of Control Offer, to redeem all of the Notes that remain Outstanding following such purchase at a purchase price equal to the Change of Control Payment plus, to the extent not included in the Change of Control Payment, accrued and unpaid interest on the Notes that remain Outstanding, to the date of redemption (subject to the right of Holders on the relevant record date to receive interest due on the relevant interest payment date that is on or prior to such date of redemption).

The Company shall not, and the Company shall not permit any of its Subsidiaries, either directly or indirectly, to pay (or cause to be paid) any consideration, whether by way of interest, fee or otherwise, to any Beneficial Owner or Holder of the Notes for or as an inducement to any consent to any waiver, supplement or amendment of any terms or provisions of this Indenture or the Notes, unless such consideration is offered to be paid (or agreed to be paid) to all Beneficial Owners and Holders of the Notes which so consent in the time frame set forth in the solicitation documents relating to such consent.

The Board of Directors of the Company may designate any Restricted Subsidiary of the Company to be an Unrestricted Subsidiary if that designation would not cause a Default. If a Restricted Subsidiary of the Company is designated as an Unrestricted Subsidiary, the aggregate Fair Market Value of all outstanding Investments owned by the Company and its Restricted Subsidiaries in the Subsidiary properly designated as an Unrestricted Subsidiary will be deemed to be an Investment made as of the time of the designation and will reduce the amount available for Restricted Payments under Section 4.09 or represent Permitted Investments, as determined by the Company. That designation shall only be permitted if the Investment would be permitted at that time and if the Subsidiary so designated otherwise meets the definition of an Unrestricted Subsidiary.

The Board of Directors of the Company may at any time designate any Unrestricted Subsidiary of the Company to be a Restricted Subsidiary of the Company; provided that such designation will be deemed to be an incurrence of Indebtedness by a Restricted Subsidiary of the Company of any outstanding Indebtedness of such Unrestricted Subsidiary and such designation will only be permitted if (1) such Indebtedness is permitted under Section 4.11, calculated on a pro forma basis as if such designation had occurred at the beginning of the four-quarter reference period, and (2) no Default (other than a Reporting Default) or Event of Default would be in existence following such designation.

(a) Whether or not required by the SEC, so long as any Notes are Outstanding, the Company will file with the SEC for public availability within the time periods specified in the SEC’s rules and regulations taking into account any extension of time, deemed filing date or safe harbor contemplated or provided for by Rule 12b-25, Rule 13a-11(c) and Rule 15d-11(c) under the Exchange Act or General Instruction I.A.3(b) of Form S-3 under the Securities Act, and successor provisions (unless the SEC will not accept such a filing, in which case the Company will furnish to the Trustee and, upon its prior request, to any of the Holders of the Notes, within the time periods specified in the SEC’s rules and regulations):

(1) all quarterly and annual financial information with respect to the Company and its Subsidiaries that would be required to be contained in a filing with the SEC on Forms 10-Q and 10-K if the Company were required to file such Forms, including a “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and, with respect to the annual information only, a report on the annual financial statements by the Company’s certified independent accountants; and

(2) all current reports that would be required to be filed with the SEC on Form 8-K if the Company were required to file such reports.

In addition, the Company agrees that, for so long as any Notes remain outstanding and are “restricted securities” within the meaning of Rule 144(a)(3), if at any time it is not required to file the reports required by the preceding paragraph with the SEC, it will furnish to the Holders of the Notes and to securities analysts and prospective investors in the Notes, upon their request, the information required to be delivered pursuant to Rule 144A(d)(4) under the Securities Act. The Company will be deemed to have provided such information to the Trustee, Holders of the Notes and to securities analysts and prospective investors in the Notes if it has filed such reports or reports containing such information with the SEC via the EDGAR filing system and such reports are publicly available.

(b) In the event that: (1) the rules and regulations of the SEC permit the Company and any direct or indirect parent entity of the Company to report at such parent entity’s level on a consolidated basis

and such parent entity of the Company is not engaged in any business in any material respect other than incidental to its ownership, directly or indirectly, of the Capital Stock of the Company, or (2) any direct or indirect parent entity of the Company becomes a guarantor of the Notes, such consolidated reporting at such parent entity’s level in a manner consistent with that described in this Section 4.19 for the Company will satisfy this Section 4.19; provided that, such financial information is accompanied by consolidating information that explains in reasonable detail the differences between the information relating to such direct or indirect parent entity and any of its Subsidiaries other than the Company and its Subsidiaries, on the one hand, and the information relating to the Company and its Subsidiaries on a standalone basis, on the other hand.

(c) Delivery of reports, information and documents to the Trustee under this Section 4.19 is for informational purposes only and the Trustee’s receipt of the foregoing shall not constitute constructive notice of any information contained therein or determinable from information contained therein.

(a) Sections 6.01 and 6.02 of the Original Indenture are hereby amended and restated in their entirety as follows with respect to the Notes:

An “Event of Default” occurs if one of the following shall have occurred and be continuing (whatever the reason for such Event of Default and whether it shall be involuntary or be effected by operation of law):

(1) the Company defaults in the payment when due of interest with respect to the Notes, and such default continues for a period of 30 days;

(2) the Company defaults in the payment of the principal of or premium, if any, on the Notes when due at their Stated Maturity, upon optional redemption, upon required repurchase, upon acceleration or otherwise;

(3) the Company fails to comply with the provisions of Section 5.01 hereof or to consummate a purchase of Notes when required pursuant to the provisions of Section 3.13, 4.12 or 4.16 hereof;

(4) the Company fails to comply with the provisions of Section 4.19 for 120 days after notice to the Company by the Trustee or the Holders of at least 25% in principal amount of the Notes then Outstanding of such failure;

(5) the Company fails to comply with any other covenant or other agreement in this Indenture or the Notes (including the provisions of Section 3.13, 4.12 or 4.16 to the extent not described in clause (3) of this Section 6.01) for 60 days after notice to the Company by the Trustee or the Holders of at least 25% in principal amount of the Notes then Outstanding of such failure;

(6) a default occurs under any mortgage, indenture or instrument under which there may be issued or by which there may be secured or evidenced any Indebtedness for money borrowed by the Company or any of its Restricted Subsidiaries (or the payment of which is guaranteed by the Company or any of its Restricted Subsidiaries), whether such Indebtedness or guarantee now exists or is created after the Initial Issuance Date, if such default:

(A) is caused by a failure to pay principal of, or interest or premium, if any, on such Indebtedness prior to the expiration of any grace period provided in such Indebtedness (a “Payment Default”); or

(B) results in the acceleration of such Indebtedness prior to its Stated Maturity

and, in each case, the principal amount of any such Indebtedness, together with the principal amount of any other such Indebtedness under which there has been a Payment Default or the maturity of which has been so accelerated, aggregates $30.0 million or more; provided, however, that if any such default is cured or waived or any such acceleration rescinded, or such Indebtedness is repaid and the Notes have not been accelerated, such Event of Default shall be automatically rescinded, so long as such rescission does not conflict with any judgment or decree;

(7) the Company or any of its Restricted Subsidiaries fails to pay final judgments aggregating in excess of $30.0 million (to the extent not covered by insurance by a reputable and creditworthy insurer as to which the insurer has not disclaimed coverage), which judgments are not paid, discharged or stayed for a period of 60 consecutive days;

(8) (A) any Subsidiary 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 (B) any Subsidiary Guarantor, or any Person acting on behalf of any Subsidiary Guarantor, denies or disaffirms its obligations under its Subsidiary Guarantee, except, in each case, by reason of the release of such Subsidiary Guarantee in accordance with the provisions of this Indenture;

(9) the Company, any of the Company’s Restricted Subsidiaries that is a Significant Subsidiary of the Company or any group of Restricted Subsidiaries of the Company that, taken as a whole, would constitute a Significant Subsidiary of the Company, pursuant to or within the meaning of Bankruptcy Law:

(B) consents in writing to the entry of an order for relief against it in an involuntary case,

(E) admits in writing it generally is not paying its debts as they become due; or

(10) a court of competent jurisdiction enters an order or decree under any Bankruptcy Law that:

(A) is for relief against the Company, any of the Company’s Restricted Subsidiaries that is a Significant Subsidiary of the Company or any group of Restricted Subsidiaries of the Company that, taken as a whole, would constitute a Significant Subsidiary of the Company, in an involuntary case;

(B) appoints a Custodian (x) of the Company, any of the Company’s Restricted Subsidiaries that is a Significant Subsidiary of the Company or any group of Restricted Subsidiaries of the Company that, taken as a whole, would constitute a Significant Subsidiary of the Company, or (y) for all or substantially all of the property of the Company, any of the Company’s Restricted Subsidiaries that is a Significant Subsidiary of the Company or any group of Restricted Subsidiaries of the Company, that, taken together, would constitute a Significant Subsidiary of the Company; or

(C) orders the liquidation of the Company, any of the Company’s Restricted Subsidiaries that is a Significant Subsidiary of the Company or any group of Restricted Subsidiaries of the Company that, taken as a whole, would constitute a Significant Subsidiary of the Company;

If any Event of Default occurs and is continuing, the Trustee, by notice to the Company, or the Holders of at least 25% in principal amount of the then Outstanding Notes, by notice to the Company and the Trustee, may declare all the Notes to be due and payable immediately. Upon any such declaration, the Notes shall become due and payable immediately, together with all accrued and unpaid interest, if any, and premium, if any, thereon. Notwithstanding the preceding, if an Event of Default specified in clause (9) or (10) of Section 6.01 hereof occurs with respect to the Company, any of the Company’s Restricted Subsidiaries that is a Significant Subsidiary of the Company or any group of Restricted Subsidiaries of the Company that, taken together, would constitute a Significant Subsidiary of the Company, all Outstanding Notes shall become due and payable immediately without further action or notice, together with all accrued and unpaid interest, if any, and premium, if any, thereon. The Holders of a majority in principal amount of the then Outstanding Notes by notice to the Trustee may on behalf of all of the Holders rescind an acceleration and its consequences if the rescission would not conflict with any judgment or decree and if all existing Events of Default (except with respect to nonpayment of principal, interest or premium, if any, that have become due solely because of the acceleration) have been cured or waived.

(b) Section 6.04 of the Original Indenture is hereby amended and restated in its entirety as follows:

Holders of a majority in principal amount of the then Outstanding Notes by notice to the Trustee may on behalf of the Holders of all of the Notes waive (including, without limitation, in connection with a purchase of, or tender offer or exchange offer for, Notes) any existing Default or Event of Default and its consequences hereunder, except (i) a continuing Default or Event of Default in the payment of the principal of, or interest or premium, if any, on, the Notes or (ii) as provided in Section 9.02. Upon any such waiver, such Default shall cease to exist, and any Event of Default arising therefrom shall be deemed to have been cured for every purpose of this Indenture; but no such waiver shall extend to any subsequent or other Default or impair any right consequent thereon.

(c) Section 6.05 of the Original Indenture is hereby amended by replacing the words “clause (1), (2), (3) or (7) of Section 6.01” with the words “Section 6.01” in the first sentence thereof.

(a) Section 10.01(d) of the Original Indenture is amended to replace “The obligations of” at the beginning of such section with “To the fullest extent allowed under Applicable Law, the obligations of”.

(b) Section 10.01(e) of the Original Indenture is amended to replace “Each of the Subsidiary Guarantors hereby” at the beginning of such section with “To the fullest extent allowed under Applicable Law, each of the Subsidiary Guarantors hereby”.

(c) Section 10.04 of the Original Indenture is hereby amended and restated in its entirety as follows with respect to the Notes:

Notwithstanding any other provisions of this Indenture, the Subsidiary Guarantee of a Subsidiary Guarantor shall be released: (1) in connection with any sale or other disposition of all or substantially all of the assets of such Subsidiary Guarantor (including by way of merger or consolidation) to a Person that is

not (either before or after giving effect to such transaction) the Company or a Restricted Subsidiary of the Company, if the sale or other disposition complies with Section 4.12; (2) in connection with any sale or other disposition of the Capital Stock of such Subsidiary Guarantor to a Person that is not (either before or after giving effect to such transaction) the Company or a Restricted Subsidiary of the Company, if the sale or other disposition complies with Section 4.12 and such Subsidiary Guarantor no longer qualifies as a Subsidiary as a result of such disposition; (3) if such Subsidiary Guarantor is a Restricted Subsidiary and the Company designates such Subsidiary Guarantor as an Unrestricted Subsidiary in accordance with Section 4.18 of this Indenture; (4) upon legal or covenant defeasance or discharge in accordance with Article VIII; (5) upon the liquidation or dissolution of such Subsidiary Guarantor provided no Default or Event of Default has occurred or is continuing; (6) at such time as such Subsidiary Guarantor ceases both (x) to guarantee any other Indebtedness of the Company and any Indebtedness of any other Restricted Subsidiary (except as a result of payment under any such other guarantee) and (y) to be an obligor with respect to any Indebtedness under any Credit Facility; or (7) upon such Subsidiary Guarantor consolidating with, merging into or transferring all of its assets to the Company or another Subsidiary Guarantor, and as a result of, or in connection with, such transaction such Subsidiary Guarantor dissolving or otherwise ceasing to exist.

Upon delivery by the Company to the Trustee of an Officers’ Certificate to the effect that any of the conditions described in the foregoing clauses (1) – (7) has occurred, the Trustee shall execute any documents reasonably requested by the Company in order to evidence the release of any Subsidiary Guarantor from its obligations under its Subsidiary Guarantee. Any Subsidiary Guarantor not released from its obligations under its Subsidiary Guarantee shall remain liable for the full amount of principal of and interest and premium, if any, on, the Notes and for the other obligations of such Subsidiary Guarantor under this Indenture as provided in this Article X.

(d) Article X of the Original Indenture is hereby amended by adding the following Section 10.06 with respect to the Notes:

(a) No Subsidiary Guarantor shall sell or otherwise dispose of, in one or more related transactions, all or substantially all of its assets to, or consolidate with or merge with or into (whether or not such Subsidiary Guarantor is the surviving Person), another Person (other than the Company or another Subsidiary Guarantor), unless, (i) either (1) the Person acquiring the assets in any such sale or other disposition or the Person formed by or surviving any such consolidation or merger (if other than such Subsidiary Guarantor) unconditionally assumes, pursuant to a supplemental indenture substantially in the form of Annex B hereto, all the obligations of such Subsidiary Guarantor under the Notes, this Indenture and its Subsidiary Guarantee on terms set forth herein and therein, or (2) such transaction or series of related transactions complies with the provisions of Section 4.12, and (ii) immediately after giving effect to such transaction or series of related transactions, no Default or Event of Default exists.

(b) In the case of any such consolidation or merger and upon the assumption by the successor Person, by supplemental indenture, executed and delivered to the Trustee and substantially in the form of Annex B hereto, of the Subsidiary Guarantee of, and compliance with Section 10.6(a) of the Indenture by, the applicable Subsidiary Guarantor, such successor Person shall succeed to and be substituted for such Subsidiary Guarantor with the same effect as if it had been named herein as a Subsidiary Guarantor.

(a) The third paragraph of Section 2.08 of the Original Indenture shall be amended with respect to the Notes to delete “(except as otherwise expressly permitted herein)” and to replace “Business Days” with “days”.

(b) Clause (3) of Section 6.06 of the Original Indenture shall be amended with respect to the Notes to add “to be incurred in compliance with such request” at the end of such clause.

(c) Section 8.01(b) of the Original Indenture shall be amended with respect to the Notes to delete the phrase “and the Subsidiary Guarantors’ respective” from the second paragraph thereof.

(d) The third paragraph of Section 8.01(b) shall be amended with respect to the Notes to replace the phrase “those surviving obligations specified above” with “those surviving obligations of the Company specified above”.

(e) Section 8.01(b) of the Original Indenture shall be amended with respect to the Notes to add the following paragraph after the first paragraph of such Section:

In addition, the Company shall have delivered to the Trustee an Officers’ Certificate stating that the deposit was not made by the Company with the intent of preferring the Holders over the other creditors of the Company or the Subsidiary Guarantors or with the intent of defeating, hindering, delaying or defrauding creditors of the Company, the Subsidiary Guarantors or others.

(f) Clause (8) of Section 9.01 of the Original Indenture shall be amended with respect to the Notes to replace the phrase “conform the provisions of this Indenture to the description of any Security” with the phrase “conform the provisions of this Indenture and the Securities to the description of the Indenture or any Security”.

(g) Clause (3) of Section 9.02 of the Original Indenture shall be amended and restated with respect to the Notes in its entirety to read as follows:

“(3) reduce the principal of, any premium on, or change the Stated Maturity of, any Note;”

(g) Clause (10) of Section 9.02 of the Original Indenture shall be amended with respect to the Notes to delete “materially”.

(h) The third paragraph of Section 9.04 of the Original Indenture shall be amended with respect to the Notes to replace “clauses (1) through (9)” with “clauses (1) through (10)”.

(i) The last sentence of Section 10.03 of the Original Indenture shall be amended with respect to the Notes to replace “federal or state law” with “applicable law.”

This Sixteenth Supplemental Indenture constitutes an integral part of the Indenture.

(a) capitalized terms used herein without definition shall have the meanings specified in the Indenture; and

(b) the terms “herein,” “hereof,” “hereunder,” and other words of similar import refer to this Sixteenth Supplemental Indenture.

The Original Indenture, as supplemented and amended by this Sixteenth Supplemental Indenture, is in all respects hereby adopted, ratified and confirmed.

The Trustee shall not be responsible in any manner whatsoever for or in respect of the sufficiency of this Sixteenth Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the Company and the Subsidiary Guarantors named herein.

This Sixteenth Supplemental Indenture may be executed in any number of counterparts, each of which when so executed shall be deemed an original; and all such counterparts shall together constitute but one and the same instrument.

THIS SIXTEENTH SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

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


CARRIZO OIL & GAS, INC.

By:	/s/ David L. Pitts
	Name:	David L. Pitts
	Title:	Vice President and Chief Financial Officer

BANDELIER PIPELINE HOLDING, LLC
CARRIZO (EAGLE FORD) LLC
CARRIZO (MARCELLUS) LLC
CARRIZO (MARCELLUS) WV LLC
CARRIZO (NIOBRARA) LLC
CARRIZO (UTICA) LLC
CARRIZO MARCELLUS HOLDING INC.
CLLR, INC.
HONDO PIPELINE, INC.
MESCALERO PIPELINE, LLC

By:	/s/ David L. Pitts
	Name:	David L. Pitts
	Title:	Vice President and Chief Financial Officer


WELLS FARGO BANK, NATIONAL ASSOCIATION,
as Trustee

By:	/s/ Patrick Giordano
	Name:	Patrick Giordano
	Title:	Vice President

(a) Definitions. For the purposes of this Appendix the following terms shall have the meanings indicated below:

“Depositary” means The Depository Trust Company, its nominees and their respective successors.

“Notes Custodian” means the custodian with respect to a Global Note (as appointed by the Depositary), or any successor Person thereto and shall initially be the Trustee.

(a) Form and Dating. Initial Notes shall be issued initially in the form of one or more permanent global Notes in definitive, fully registered form without interest coupons with the global Notes legend set forth in Annex A to this Sixteenth Supplemental Indenture (each, a “Global Note”), which shall be deposited on behalf of the purchasers of the Initial Notes represented thereby with the Trustee, as custodian for the Depositary (or with such other custodian as the Depositary may direct), and registered in the name of the Depositary or a nominee of the Depositary, duly executed by the Company and authenticated by the Trustee as hereinafter provided. Beneficial interests in a Global Note representing Initial Notes may be held through the Depositary. The aggregate principal amount of the Global Notes may from time to time be increased or decreased by adjustments made on the records of the Trustee and the Depositary or its nominee as hereinafter provided. Additional Notes shall be issued in global form (with the global Notes legend set forth in Annex A) or in certificated form as provided in the Indenture. Notes issued in global form are sometimes referred to in this Appendix as “Global Notes.” The Global Notes are “Global Securities” within the meaning of the Indenture, and shall be subject to the further provisions of the Indenture with respect thereto.

(b) Book-Entry Provisions. This Section 2.01(b) shall apply only to a Global Note deposited with or on behalf of the Depositary. The Company shall execute and the Trustee shall, in accordance with this Section 2.01(b) and the Indenture, authenticate and deliver initially one or more Global Notes that (a) shall be registered in the name of the Depositary for such Global Note or Global Notes or the nominee of such Depositary and (b) shall be delivered by the Trustee to such Depositary or pursuant to such Depositary’s instructions or held by the Trustee as custodian for the Depositary.

Members of, or participants in, the Depositary (“Agent Members”) shall have no rights under this Indenture with respect to any Global Note held on their behalf by the Depositary or by the Trustee as the custodian of the Depositary or under such Global Note, and the Company, the Trustee and any agent of the Company or the Trustee shall be entitled to treat the Depositary as the absolute owner of such Global Note for all purposes whatsoever. Notwithstanding the foregoing, nothing herein shall prevent the Company, the Trustee or any agent of the Company or the Trustee from giving effect to any written certification, proxy or other authorization furnished by the Depositary or impair, as between the Depositary and its Agent Members, the operation of customary practices of such Depositary governing the exercise of the rights of a holder of a beneficial interest in any Global Note.

(a) The transfer and exchange of Global Notes or beneficial interests therein shall be effected through the Depositary, in accordance with this Indenture (including applicable restrictions on transfer set forth herein, if any) and the procedures of the Depositary therefor. A transferor of a beneficial interest in a Global Note shall deliver to the Registrar a written order given in accordance with the Depositary’s procedures containing information regarding the participant account of the Depositary to be credited with a beneficial interest in the Global Note. The Registrar shall, in accordance with such instructions, instruct the Depositary to credit to the account of the Person specified in such instructions a beneficial interest in the Global Note and to debit the account of the Person making the transfer the beneficial interest in the Global Note being transferred.

(b) Notwithstanding any other provisions of this Appendix, a Global Note may not be transferred as a whole except 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.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS MADE TO CEDE & CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY, THIS GLOBAL NOTE 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.

Carrizo Oil & Gas, Inc., a Texas corporation (herein called the “Company,” which term includes any successor entity under the indenture hereinafter referred to), for value received, hereby promises to pay to [ ], or registered assigns, the principal sum of [ ] United States Dollars ($[ ]) (or such other amount as is reflected on the attached Schedule of Increases or Decreases of Global Security) on April 15, 2023 and to pay interest thereon in immediately available funds as specified on the other side of this Note.

If a Holder of this Note has given wire transfer instructions for a United States account to the Company, the Company will pay all principal, interest and premium, if any on this Note in accordance with such instructions. Otherwise, payment of the principal, interest and premium, if any, on this Note will be made at the office or agency of the Company maintained for that purpose in Dallas, Texas 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; provided, however, that at the option of the Company, payment of interest may be made by check mailed to the address of the Person entitled thereto as such address shall appear in the register of Notes unless the Holder has given wire transfer instructions to the Company to an account in the United States.

Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.


CARRIZO OIL & GAS, INC.

By:
		Name:
		Title:

By:
		Name:
		Title:

This is one of the Notes of the series designated therein referred to in the within-mentioned Indenture.

WELLS FARGO BANK, NATIONAL ASSOCIATION,

as Trustee

Authorized Signatory

This Note is one of a duly authorized issue of Notes of the Company issued and to be issued in one or more series under an Indenture, dated as of May 28, 2008, as amended by the Sixteenth Supplemental Indenture thereto dated as of April 28, 2015 (as so amended, herein called the “Indenture”), among the Company, the Subsidiary Guarantors named therein and Wells Fargo Bank, National Association, as trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), or their respective predecessors, as applicable, to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Subsidiary Guarantors, the Trustee and the Holders of the Notes and of the terms upon which the Notes are, and are to be, authenticated and delivered. This Note is one of the series designated on the face hereof, which is initially in the aggregate principal amount of $[ ]. As used herein, the term “Notes” means the Company’s 6.250% Senior Notes due 2023 issued under the Indenture.

Subject to Section 2.18 of the Indenture, the Company may, at any time and from time to time, without notice or the consent of the holders of the Notes, create and issue Additional Notes ranking equally and ratably with the Notes in all respects (except for the payment of interest accruing prior to the date such Additional Notes are initially issued under the Indenture and the offering price and issue date), so that such Additional Notes form a single series with such Notes and have the same terms as to status, redemption, covenants or otherwise as such Notes.

The rate at which this Note shall bear interest shall be 6.250% per annum. Interest on this Note shall accrue from [April 28, 2015 in the case of Notes issued on the Initial Issuance Date], or from the most recent date to which interest has been paid or provided for on the Notes. The Interest Payment Dates on which interest on this Note shall be payable are April 15 and October 15 of each year (each, an “Interest Payment Date”), commencing on [October 15, 2015, in the case of the Notes issued on the Initial Issuance Date]. If an Interest Payment Date falls on a day that is not a Business Day, the interest payment to be made on such Interest Payment Date will be made on the next succeeding Business Day with the same force and effect as if made on such Interest Payment Date, and no additional interest will accrue solely as a result of such delayed payment. The Regular Record Date for the interest payable on this Note on any Interest Payment Date shall be the April 1 or October 1, as the case may be, immediately preceding such Interest Payment Date. Interest will cease to accrue on this Note upon its maturity, purchase by the Company at the option of a holder or redemption. Interest will be computed on the basis of a 360-day year comprised of twelve 30-day months.

Payments in respect of principal of and interest, if any, on the Notes shall be made by the Company in immediately available funds.

(a) Except as set forth in subparagraphs (b) and (c) of this section or in the final paragraph of Section 4.16 of the Indenture, the Company shall not have the option to redeem this Note prior to April 15, 2018. On and after April 15, 2018, the Company shall have the option to redeem this Note, in whole or in part at any time, upon prior notice as set forth below under the caption “Notice,” at the Redemption Prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on this Note to the applicable Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on an Interest Payment Date that is on or prior to the Redemption Date), if redeemed during the twelve-month period beginning on April 15 of the years indicated below:

(b) Notwithstanding the provisions of subparagraph (a) of this section, at any time prior to April 15, 2018, the Company may on one or more occasions redeem up to 35% of the aggregate principal amount of the Notes at a Redemption Price of 106.250% of the principal amount thereof, plus accrued and unpaid interest, if any, thereon to the Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on an Interest Payment Date that is on or prior to the Redemption Date), in an amount up to the amount of the net cash proceeds of one or more Equity Offerings; provided that, with respect to each such redemption, (i) at least 65% of the aggregate principal amount of the Notes initially issued under the Indenture remains outstanding immediately after the occurrence of such redemption (excluding any Notes held by the Company and its Subsidiaries) and (ii) such redemption occurs within 180 days of the date of the closing of the related Equity Offering.

(c) Prior to April 15, 2018, the Company may redeem on one or more occasions all or part of this Note at a Redemption Price equal to the sum of (1) 100% of the principal amount thereof, plus (2) accrued and unpaid interest, if any, to the Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the Redemption Date), plus (3) the Make Whole Premium at the Redemption Date.

If less than all of the Notes are to be redeemed at any time, the Trustee will select Notes for redemption as follows:

(1) if the Notes are listed on any national securities exchange, in compliance with the requirements of the principal national securities exchange on which the Notes are listed; or

(2) if the Notes are not listed on any national securities exchange, on a pro rata basis or, in the case of Notes issued in global form, the Trustee will select Notes for redemption based on DTC’s method that most nearly approximates a pro rata selection unless otherwise required by law.

No Note of $2,000 or less can be redeemed in part. Notices of optional redemption will be mailed by first class mail or, if the Notes are in global form, sent pursuant to the applicable procedures of DTC, at least 30 but not more than 60 days before the Redemption Date to each Holder of Notes to be redeemed at its registered address, except that optional redemption notices may be sent more than 60 days prior to a Redemption Date if the notice is issued in connection with a defeasance of the Notes or a discharge of the indenture. 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 a related Equity Offering.

If this Note is to be redeemed in part only, the notice of redemption that relates to this Note will state the portion of the principal amount that is to be redeemed. A Note in principal amount equal to the unredeemed portion of this Note will be issued in the name of the applicable Holder upon cancellation of this Note. Notes called for redemption become due on the date fixed for redemption, subject to satisfaction of any condition to the redemption. On and after the Redemption Date, interest ceases to accrue on Notes or portions of them called for redemption.

The notice of redemption with respect to a redemption described in Paragraph (c) under the caption “Optional Redemption” need not set forth the Make Whole Premium but only the manner of calculation thereof.

If a Change of Control occurs, the Holder of this Note will have the right to require the Company to repurchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess of $2,000) of this Note pursuant to an offer (“Change of Control Offer”) on the terms set forth in the Indenture. In the Change of Control Offer, the Company will offer a payment in cash (the “Change of Control Payment”) equal to 101% of the aggregate principal amount of the part of this Note repurchased plus accrued and unpaid interest, if any, to the date of purchase (the “Change of Control Purchase Date”), subject to the right of the Holders of record of this Note on the relevant record date to receive interest due on an interest payment date that is on or prior to the Change of Control Purchase Date.

In the event that Holders of not less than 90% of the aggregate principal amount of the outstanding Notes accept a Change of Control Offer and the Company purchases all of the Notes held by such Holders, the Company will have the right to redeem all of the Notes that remain outstanding following such purchase on the terms set forth in the Indenture.

Subject to the terms of the Indenture, in certain circumstances, the Company may be required to make an offer (the “Asset Sale Offer”) to all Holders of Notes, and to all holders of Pari Passu Indebtedness then outstanding, to purchase the maximum principal amount of Notes and such Pari Passu Indebtedness that may be purchased out of the Excess Proceeds. The offer price in any Asset Sale Offer will be equal to 100% of principal amount plus accrued and unpaid interest, if any, to the date of settlement, subject to the right of Holders of record on the relevant record date to receive interest due on an Interest Payment Date that is on or prior to the date of settlement, and will be payable in cash.

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the register of the Notes, upon surrender of this Note for registration or transfer at the office or agency of the Registrar for the Notes, duly endorsed by, or accompanied by a written instrument of transfer in form reasonably satisfactory to the Registrar duly executed by the Holder thereof or his attorney duly authorized in writing, and thereupon one or more new Notes, of like tenor and of other authorized denominations and for the same aggregate principal amount, executed by the Company and authenticated and delivered by the Trustee, will be issued to the designated transferee or transferees.

The Notes are issuable only in registered form without coupons in denominations of $2,000 and integral multiples of $1,000, in excess of $2,000. As provided in the Indenture and subject to certain limitations set forth therein and on the face of this Note, Notes are exchangeable for a like aggregate principal amount of Notes of a different authorized denomination as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Note for registration of transfer, the Company, the Trustee or any agent of the Company or the Trustee may treat the Person in whose name this Note is registered as the owner hereof for all purposes, whether or not this Note be overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

The payment by the Company of the principal of and interest and premium, if any, on the Notes is fully and unconditionally guaranteed on a joint and several senior unsecured basis by each of the Subsidiary Guarantors to the extent set forth in the Indenture.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Holders of the Notes at any time by the Company and the Trustee with the consent of the Holders of at least a majority in principal amount of the then outstanding Notes. The Indenture also contains provisions permitting the Holders of at least a majority in principal amount of the then outstanding Notes, to waive compliance by the Company with certain existing or past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange hereof or in lieu hereof, whether or not notation of such consent or waiver is made upon this Note.

When a successor Person assumes all the obligations of its predecessor under the Notes and the Indenture in accordance with the terms and conditions of the Indenture, the predecessor Person will (except in certain circumstances specified in the Indenture) be released from those obligations.

If an Event of Default with respect to Notes shall occur and be continuing, all unpaid principal amount plus accrued and unpaid interest through the acceleration date of the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

No director, officer, partner, employee, incorporator, manager or shareholder or other owner of Capital Stock of the Company or any Subsidiary Guarantor, as such, will have any liability for any obligations of the Company or any Subsidiary Guarantor under the Notes, the Indenture or the Subsidiary Guarantees, 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.

In the case of any conflict between the provisions of this Note and the Indenture, the provisions of the Indenture shall control.

THE INDENTURE AND THE NOTES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

All terms defined in the Indenture and used in this Note but not specifically defined herein are used herein as so defined.

To assign this Note, fill in the form below and have your signature guaranteed: (I) or (we) assign and transfer this Note to:

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

If you want to elect to have this Note purchased, in whole or in part, by the Company pursuant to Section 4.12 or 4.16 of the Indenture, check the following box:

If you want to have only part of this Note purchased by the Company pursuant to Section 4.12 or 4.16 of the Indenture, state the principal amount you want to be purchased (in minimum denomination of $2,000 or integral multiples of $1,000 in excess of $2,000): $

Each of the Subsidiary Guarantors (which term includes any successor Person under the Indenture) has fully, unconditionally and absolutely guaranteed, to the extent set forth in the Indenture and subject to the provisions in the Indenture, the due and punctual payment of the principal of, and premium, if any, and interest on the Notes and all other amounts due and payable under the Indenture and the Notes by the Company.

The obligations of the Subsidiary Guarantors to the Holders of Notes and to the Trustee pursuant to the Guarantee and the Indenture are expressly set forth in Article X of the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee.


[NAME OF SUBSIDIARY GUARANTOR]

By:
		Name:
		Title:

THIS SUPPLEMENTAL INDENTURE, dated as of , , among Carrizo Oil and Gas, Inc., a Texas corporation (the “Company”), [ ] (the “Guaranteeing Subsidiary”), which is a subsidiary of the Company, each of the existing Subsidiary Guarantors (as defined in the Indenture referred to below) and Wells Fargo Bank, National Association, as trustee (the “Trustee”).

WHEREAS, the Company, certain of its Subsidiaries and the Trustee heretofore executed and delivered an Indenture, dated as of May 28, 2008 (as amended and supplemented by a Sixteenth Supplemental Indenture among the Company, certain of its Subsidiaries, and the Trustee, dated as of April 28, 2015, the “Indenture”), providing for the issuance of the Company’s 6.250% Senior Notes due 2023 (the “Notes”);

WHEREAS, Section 4.15 of the Indenture provides that under certain circumstances a Restricted Subsidiary of the Company that is not already a Subsidiary Guarantor shall execute and deliver to the Trustee a supplemental indenture pursuant to which such Restricted Subsidiary shall become a Subsidiary Guarantor; and

WHEREAS, the Company, pursuant to the terms and provisions of the Indenture, proposes in and by this Supplemental Indenture to supplement and amend the Indenture insofar as it will apply only to the Notes in certain respects;

To comply with the provisions of the Indenture and in consideration of the premises provided for herein, the Guaranteeing Subsidiary, the Company, the existing Subsidiary Guarantors and the Trustee mutually covenant and agree for the equal and proportionate benefit of all Holders of the Notes as follows:

The Guaranteeing Subsidiary hereby agrees by execution of this Supplemental Indenture, with respect to the Notes, to be bound by all of the provisions of the Indenture applicable to a Subsidiary Guarantor to the extent provided for in Article X of the Indenture.

(a) capitalized terms used herein without definition shall have the meanings specified in the Indenture; and

(b) the terms “herein,” “hereof,” “hereunder” and other words of similar import refer to this Supplemental Indenture.

The Indenture, as supplemented and amended by this Supplemental Indenture, is in all respects hereby adopted, ratified and confirmed.

The Trustee shall not be responsible in any manner whatsoever for or in respect of the sufficiency of this Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the Company and the Subsidiary Guarantors named herein.

This [ ] Supplemental Indenture may be executed in any number of counterparts, each of which when so executed shall be deemed an original; and all such counterparts shall together constitute but one and the same instrument.

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

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


CARRIZO OIL & GAS, INC.

By:
		Name:
		Title:

GUARANTEEING SUBSIDIARY
[ ]

By:
		Name:
		Title:

EXISTING SUBSIDIARY GUARANTORS¹

By:
		Name:
		Title:

WELLS FARGO BANK, NATIONAL ASSOCIATION, as Trustee

By:
		Name:
		Title:


		Page

ARTICLE ONE THE NOTES			2

SECTION 101	Designation of Notes; Establishment of Form		2
SECTION 102	Amount		2
SECTION 103	Interest		2
SECTION 104	Denominations		3
SECTION 105	Place of Payment		3
SECTION 106	Redemption		3
SECTION 107	Maturity		3
SECTION 108	Repurchase		3
SECTION 109	[Reserved]		3
SECTION 110	Guarantee		3
SECTION 111	Other Terms of Notes		3

ARTICLE TWO AMENDMENTS TO THE INDENTURE			4

SECTION 201	Definitions		4
SECTION 202	Other Definitions		31
SECTION 203	Mutilated, Destroyed, Lost and Stolen Securities		31
SECTION 204	Amendment of Indenture Without Consent of Holders		31
SECTION 205	Limitation on Mergers and Consolidations		31
SECTION 206	Issuance of Additional Notes		33
SECTION 207	Redemption		33
SECTION 208	Covenants		36
SECTION 209	Amendment to Events of Default		55
SECTION 210	Guarantees		57
SECTION 211	Other Amendments		58

ARTICLE THREE MISCELLANEOUS PROVISIONS			59

SECTION 301	Integral Part		59
SECTION 302	General Definitions		59
SECTION 303	Adoption, Ratification and Confirmation		59
SECTION 304	The Trustee		60
SECTION 305	Counterparts		60
SECTION 306	Governing Law		60


Appendix 1 – Provisions Relating to the Notes							Appendix-1
Annex A – Form of Global Securities							A-1
Annex B – Form of Supplemental Indenture							B-1


YEAR	PERCENTAGE
2018		104.688	%
2019		103.125	%
2020		101.563	%
2021 and thereafter		100.000	%


Principal Amount: $		CUSIP:

Registered: No.		ISIN:


YEAR	PERCENTAGE
2018		104.688	%
2019		103.125	%
2020		101.563	%
2021 and thereafter		100.000	%


Term		Defined in Section
“Affiliate Transaction”		4.13
“Asset Sale Offer”		3.13
“Change of Control Offer”		4.16
“Change of Control Payment”		4.16
“Change of Control Purchase Date”		4.16
“Change of Control Settlement Date”		4.16
“Excess Proceeds”		4.12
“incur”		4.11
“Offer Amount”		3.13
“Offer Period”		3.13
“Payment Default”		6.01
“Permitted Debt”		4.11
“Restricted Payments”		4.09
“Settlement Date”		3.13
“Termination Date”		3.13


(a) Date of Exchange	(b) Amount of Decrease in Principal Amount of this Global Security	(c) Amount of Increase in Principal Amount of this Global Security	(d) Principal Amount of this Global Security Following such Decrease or Increase	(e) Signature of Authorized Officer of Trustee or Securities Custodian


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