Form of Master Forward Sale Confirmation

Exhibit 1.2

AGREED FORM

Dear Sir(s):

The purpose of this communication (this “Master Confirmation”) is to set forth the terms and conditions of the transactions to be entered into from time to time between [Dealer] (“Dealer”) and Atmos Energy Corporation (“Counterparty”) in accordance with the terms of the Equity Distribution Agreement, dated as of [DATE] (the “Equity Distribution Agreement”), among Counterparty and the Managers and the Forward Purchasers party thereto (as amended, modified, supplemented or restated from time to time) on the Trade Dates specified herein (collectively, the “Transactions” and each, a “Transaction”). This communication constitutes a “Confirmation” as referred to in the Agreement specified below. Each Transaction will be evidenced by a supplemental confirmation (each, a “Supplemental Confirmation”) substantially in the form of Exhibit A hereto and a written hedge completion notice (if any) furnished by Dealer (each, a “Hedge Completion Notice”, and each such Hedge Completion Notice together with the relevant Supplemental Confirmation and this Master Confirmation, a “Confirmation” for purposes of the Agreement specified below) substantially in the form of Exhibit B hereto. Each Confirmation will be a confirmation for purposes of Rule 10b-10 promulgated under the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

1. Each Confirmation incorporates the 2002 ISDA Equity Derivatives Definitions (the “Equity Definitions”), as published by the International Swaps and Derivatives Association, Inc. (“ISDA”). For purposes of the Equity Definitions, each Transaction will be deemed to be a Share Forward Transaction.

Each Confirmation shall supplement, form a part of and be subject to an agreement (the “Agreement”) in the form of the ISDA 2002 Master Agreement (the “ISDA Form”), as published by ISDA, as if Dealer and Counterparty had executed the ISDA Form on the date hereof (but without any Schedule except for the election of New York law (without regard to New York’s choice of laws doctrine other than Title 14 of Article 5 of the New York General Obligations Law (the “General Obligations Law”)) as the governing law and US Dollars (“USD”) as the Termination Currency).

All provisions contained in the Agreement are incorporated into and shall govern each Confirmation except as expressly modified below. Each Confirmation evidences a complete and binding agreement between Dealer and Counterparty as to the terms of the relevant Transaction and replaces any previous agreement between the parties with respect to the subject matter hereof.

The Transactions hereunder shall be the sole Transactions under the Agreement. If there exists any ISDA Master Agreement between Dealer or any of its Affiliates and Counterparty or any confirmation or other agreement between Dealer or any of its Affiliates and Counterparty pursuant to which an ISDA Master Agreement is deemed to exist between Dealer or any of its Affiliates and Counterparty, then notwithstanding anything to the contrary in such ISDA Master Agreement, such confirmation or agreement or any other agreement to which Dealer or such other Affiliates and Counterparty are parties, the Transactions hereunder shall not be considered transactions under, or otherwise governed by, such existing or deemed ISDA Master Agreement. In the event of any inconsistency among the Agreement, this Master Confirmation, any Supplemental Confirmation and the Equity Definitions, the following will prevail in the order of precedence indicated: (i) such Supplemental Confirmation; (ii) this Master Confirmation; (iii) the Equity Definitions; and (iv) the Agreement.

General Terms:

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Valuation:

Settlement Terms:

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Share Adjustments:

Extraordinary Events:

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Additional Disruption Events:

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Early Valuation:

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Acknowledgements:

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For the purpose of Section 12(a) of the ISDA Master Agreement:

[                 ]

For notices with respect to each Transaction:

[                 ]

3. Effectiveness.

The effectiveness of each Supplemental Confirmation and the related Transaction on the Effective Date for such Supplemental Confirmation shall be subject to satisfaction (or waiver by Dealer) of the following conditions:

(a) the representations and warranties of Counterparty contained in the Equity Distribution Agreement, and any certificate delivered pursuant thereto by Counterparty shall be true and correct on such Effective Date as if made as of such Effective Date;

(b) Counterparty shall have performed all of the obligations required to be performed by it under the Equity Distribution Agreement on or prior to such Effective Date;

(c) all of the conditions set forth in Section 5 of the Equity Distribution Agreement shall have been satisfied;

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(d) such Supplemental Confirmation shall be dated during the period commencing on the date of the Equity Distribution Agreement and expiring on the earlier to occur of (i) the date on which on which the gross sale price of Shares sold pursuant to the Equity Distribution Agreement and any similar agreement or agreements with one or more other dealers and dated the date thereof is equal to or exceeds USD1,000,000,000 and (ii) the date on which the Equity Distribution Agreement is terminated;

(e) all of the representations and warranties of Counterparty hereunder and under the Agreement shall be true and correct on such Effective Date as if made as of such Effective Date;

(f) Counterparty shall have performed all of the obligations required to be performed by it hereunder and under the Agreement on or prior to such Effective Date, including without limitation its obligations under Sections 5 and 6 hereof; and

(g) Counterparty shall have delivered to Dealer an opinion of counsel in form and substance reasonably satisfactory to Dealer, with respect to the matters set forth in Section 3(a) of the Agreement (subject to customary exceptions, limitations, qualifications and assumptions reasonably acceptable to Dealer) and that the maximum number of Shares initially issuable under such Transaction have been duly authorized and, upon issuance pursuant to the terms of such Transaction, will be validly issued, fully paid and nonassessable.

Notwithstanding the foregoing or any other provision of this Master Confirmation or any Supplemental Confirmation, if in respect of any Transaction (x) on or prior to 9:00 a.m., New York City time, on any Forward Hedge Settlement Date, in connection with establishing its commercially reasonable hedge position in respect of such Transaction Dealer, in its good faith and commercially reasonable judgment, is unable, after using commercially reasonable efforts, to borrow and deliver for sale the full number of Shares to be borrowed and sold pursuant to the Equity Distribution Agreement on such Forward Hedge Settlement Date or (y) in Dealer’s good faith and commercially reasonable judgment, it would incur a stock loan cost of more than a rate equal to the Maximum Stock Loan Rate for such Transaction with respect to all or any portion of such full number of Shares, the effectiveness of the related Supplemental Confirmation and such Transaction shall be limited to the number of Shares Dealer is so able to borrow in connection with establishing its commercially reasonable hedge position of such Transaction at a cost of not more than a rate equal to the Maximum Stock Loan Rate for such Transaction, which, for the avoidance of doubt, may be zero. “Forward Hedge Settlement Date” will mean a Trading Day that is one Settlement Cycle immediately following the Trading Day on which the sale of any Forward Hedge Shares occurs pursuant to the Equity Distribution Agreement.

4. Additional Mutual Representations and Warranties. In addition to the representations and warranties in the Agreement, each party represents and warrants to the other party that it is an “eligible contract participant”, as defined in the U.S. Commodity Exchange Act (as amended), and an “accredited investor” as defined in Section 2(a)(15)(ii) of the Securities Act of 1933 (as amended) (the “Securities Act”), and is entering into each Transaction hereunder as principal and not for the benefit of any third party.

5. Additional Representations, Warranties and Agreements of Counterparty. Counterparty represents and warrants to Dealer that the representations and warranties of Counterparty which are set forth in Section 2 of the Equity Distribution Agreement are true and correct as of the date hereof, except to the extent such representations and warranties expressly relate to any earlier date, in which case they shall have been true and correct as of such earlier date in all material respects and will be deemed to have represented and warranted to Dealer that such representations and warranties are true and correct as of the date of each Supplemental Confirmation, each Trade Date for any Transaction and each Forward Hedge Settlement Date for any Transaction. Such representations and warranties hereby are deemed to be repeated to Dealer on the date hereof and on each such other date as if set forth herein. In addition to the representations and warranties in Section 1 of the Equity Distribution Agreement, the Agreement and those contained elsewhere herein, Counterparty represents and warrants to Dealer, and agrees with Dealer, that:

(a) without limiting the generality of Section 13.1 of the Equity Definitions, it acknowledges that Dealer is not making any representations or warranties with respect to the treatment of any Transaction, including without limitation ASC Topic 260, Earnings Per Share, ASC Topic 815, Derivatives and Hedging, ASC Topic 480, Distinguishing Liabilities from Equity, ASC 815-40, Derivatives and Hedging — Contracts in Entity’s Own Equity (or any successor issue statements) or under the Financial Accounting Standards Board’s Liabilities & Equity Project;

(b) it shall not take any action to reduce or decrease the number of authorized and unissued Shares below the sum of (i) the aggregate Number of Shares across all Transactions hereunder plus (ii) the total number of Shares issuable upon settlement (whether by physical settlement, net share settlement or otherwise) of any other transaction or agreement to which it is a party;

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(c) it will not repurchase any Shares if, immediately following such repurchase, the aggregate Number of Shares across all Transactions hereunder would be equal to or greater than 4.9% of the number of then-outstanding Shares and it will notify Dealer promptly upon the announcement or consummation of any repurchase of Shares in an amount that, taken together with the amount of all repurchases since the date of the last such notice (or, if no such notice has been given, since the Trade Date), exceeds 0.5% of the number of then-outstanding Shares; it is not entering into this Master Confirmation or any Supplemental Confirmation to create actual or apparent trading activity in the Shares (or any security convertible into or exchangeable for Shares), or to raise or depress or otherwise manipulate the price of the Shares (or any security convertible into or exchangeable for Shares) for the purpose of inducing the purchase or sale of the Shares (or any security convertible into or exchangeable for Shares) by others;

(d) neither it nor any of its officers or directors is aware of any material non-public information regarding itself or the Shares; it is entering into this Master Confirmation and each Supplemental Confirmation and will provide any Settlement Notice in good faith and not as part of a plan or scheme to evade compliance with Rule 10b-5 or any other provision of the federal securities laws; it has not entered into or altered any hedging transaction relating to the Shares corresponding to or offsetting any Transaction; and it has consulted with its own advisors as to the legal aspects of its adoption and implementation of this Master Confirmation and each Supplemental Confirmation under Rule 10b5-1 under the Exchange Act (“Rule 10b5-1”);

(e) as of the date hereof and the Trade Date for each Transaction no state or local (including non-U.S. jurisdictions) law, rule, regulation or regulatory order applicable to the Shares would give rise to any reporting, consent, registration or other requirement (including without limitation a requirement to obtain prior approval from any person or entity) as a result of Dealer or its affiliates owning or holding (however defined) Shares in connection with any Transaction; provided that Counterparty makes no such representation or warranty regarding any such requirement that is applicable generally to the ownership of equity securities by Dealer;

(f) as of the date hereof, the Trade Date for each Transaction and the date of any payment or delivery by Counterparty or Dealer under any Transaction, it is not and will not be “insolvent” (as such term is defined under Section 101(32) of the Bankruptcy Code);

(g) it is not as of the date hereof, and on the Trade Date for each Transaction and after giving effect to the transactions contemplated hereby and by each Supplemental Confirmation will not be, required to register as an “investment company” as such term is defined in the Investment Company Act of 1940, as amended;

(h) as of the date hereof and the Trade Date for each Transaction it: (i) is an “institutional account” as defined in FINRA Rule 4512(c); and (ii) is capable of evaluating investment risks independently, both in general and with regard to all transactions and investment strategies involving a security or securities, and will exercise independent judgment in evaluating any recommendations of Dealer or its associated persons; and

(i) IT UNDERSTANDS AS OF THE DATE HEREOF AND AS OF THE TRADE DATE FOR EACH TRANSACTION THAT EACH TRANSACTION IS SUBJECT TO COMPLEX RISKS WHICH MAY ARISE WITHOUT WARNING AND MAY AT TIMES BE VOLATILE AND THAT LOSSES MAY OCCUR QUICKLY AND IN UNANTICIPATED MAGNITUDE AND IS WILLING TO ACCEPT SUCH TERMS AND CONDITIONS AND ASSUME (FINANCIALLY AND OTHERWISE) SUCHRISKS.

6. Additional Covenants of Counterparty.

(a) Counterparty acknowledges and agrees that any Shares delivered by Counterparty to Dealer on any Physical Settlement Date or Net Share Settlement Date for any Transaction will be (i) newly issued, (ii) approved for listing or quotation on the Exchange, subject to official notice of issuance, and (iii) registered under the Exchange Act, and, when delivered by Dealer (or an affiliate of Dealer) to securities lenders from whom Dealer (or an affiliate of Dealer) borrowed Shares in connection with hedging its exposure to such Transaction, will be freely saleable without further registration or other restrictions under the Securities Act in the hands of those securities lenders, irrespective of whether any such stock loan is effected by Dealer or an affiliate of Dealer . Accordingly, Counterparty agrees that any Shares so delivered will not bear a restrictive legend and will be deposited in, and the delivery thereof shall be effected through the facilities of, the Clearance System. In addition, Counterparty represents and agrees that any such Shares shall be, upon such delivery, duly and validly authorized, issued and outstanding, fully paid and nonassessable, free of any lien, charge, claim or other encumbrance.

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(b) Counterparty agrees that Counterparty shall not enter into or alter any hedging transaction relating to the Shares corresponding to or offsetting any Transaction. Without limiting the generality of the provisions set forth opposite the caption “Unwind Activities” in Section 2 of this Master Confirmation, Counterparty acknowledges that it has no right to, and agrees that it will not seek to, control or influence Dealer’s decision to make any “purchases or sales” (within the meaning of Rule 10b5-1(c)(1)(i)(B)(3)) under or in connection with any Transaction, including, without limitation, Dealer’s decision to enter into any hedging transactions.

(c) Counterparty acknowledges and agrees that any amendment, modification, waiver or termination of this Master Confirmation or any Supplemental Confirmation must be effected in accordance with the requirements for the amendment or termination of a “plan” as defined in Rule 10b5-1(c). Without limiting the generality of the foregoing, any such amendment, modification, waiver or termination shall be made in good faith and not as part of a plan or scheme to evade the prohibitions of Rule 10b-5, and no such amendment, modification or waiver shall be made at any time at which Counterparty or any officer, director, manager or similar person of Counterparty is aware of any material non-public information regarding Counterparty or the Shares.

(d) Counterparty shall promptly provide notice thereof to Dealer (i) upon the occurrence of any event that would constitute a Potential Event of Default, an Event of Default or a Termination Event in respect of which Counterparty is a Defaulting Party or an Affected Party, as the case may be, and (ii) upon announcement of any event that, if consummated, would constitute an Extraordinary Event or Potential Adjustment Event.

(e) Neither Counterparty nor any of its “affiliated purchasers” (as defined by Rule 10b-18 under the Exchange Act (“Rule 10b-18”)) shall take any action that would reasonably be expected to cause any purchases of Shares by Dealer or any of its Affiliates in connection with any Cash Settlement or Net Share Settlement of any Transaction not to meet the requirements of the safe harbor provided by Rule 10b-18 if such purchases were made by Counterparty. Without limiting the generality of the foregoing, during any Unwind Period for any Transaction, except with the prior written consent of Dealer, Counterparty will not, and will cause its affiliated purchasers (as defined in Rule 10b-18) not to, directly or indirectly (including, without limitation, by means of a derivative instrument) purchase, offer to purchase, place any bid or limit order that would effect a purchase of, or announce or commence any tender offer relating to, any Shares (or equivalent interest, including a unit of beneficial interest in a trust or limited partnership or a depository share) or any security convertible into or exchangeable for the Shares. However, the foregoing shall not (a) limit Counterparty’s ability, pursuant to any issuer “plan” (as defined in Rule 10b-18), to re-acquire Shares from employees in connection with such plan or program, (b) limit Counterparty’s ability to withhold Shares to cover tax liabilities associated with such a plan, (c) prohibit any purchases effected by or for an issuer “plan” by an “agent independent of the issuer” (each as defined in Rule 10b-18), (d) otherwise restrict Counterparty’s or any of its affiliates’ ability to repurchase Shares under privately negotiated, off-exchange transactions with any of its employees, officers, directors, affiliates or any third party will not result in market transactions or (e) limit Counterparty’s ability to grant stock and options to “affiliated purchasers” (as defined in Rule 10b-18) or the ability of such affiliated purchasers to acquire such stock or options in connection with any issuer “plan” (as defined in Rule 10b-18) for directors, officers and employees or any agreements with respect to any such plan for directors, officers or employees of any entities that are acquisition targets of Counterparty, and in connection with any such purchase under

(a) through (e) above, Counterparty will be deemed to represent to Dealer that such purchase does not constitute a “Rule 10b-18 purchase” (as defined in Rule 10b-18).

(f) Counterparty will not be subject to any “restricted period” (as such term is defined in Regulation M promulgated under the Exchange Act (“Regulation M”)) in respect of Shares or any security with respect to which the Shares are a “reference security” (as such term is defined in Regulation M) during any Unwind Period for any Transaction.

(g) During any Unwind Period, Counterparty shall: (i) prior to the opening of trading in the Shares on any day on which Counterparty makes, or expects to be made, any public announcement (as defined in Rule 165(f) under the Securities Act) of any Merger Transaction, to the extent permitted by applicable law, notify Dealer of such public announcement; (ii) promptly notify Dealer following any such announcement that such announcement has been made; (iii) promptly (but in any event prior to the next opening of the regular trading session on the Exchange) provide Dealer with written notice specifying (A) Counterparty’s average daily Rule 10b-18 Purchases (as defined in Rule 10b-18) during the three full calendar months immediately preceding the announcement date for the Merger Transaction that were not effected through Dealer or its affiliates and (B) the number of Shares purchased pursuant to the proviso in Rule 10b-18(b)(4) under the Exchange Act for the three full calendar months preceding such announcement date. Such written notice shall be deemed to be a certification by Counterparty to Dealer that such information is true and correct. In addition, Counterparty shall promptly notify Dealer of the earlier to occur of the completion of such transaction and the completion of the vote by target shareholders. Counterparty acknowledges

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that any such notice may result in a Regulatory Disruption, a Trading Condition or, if such notice relates to an event that is also an ISDA Event, an Early Valuation, or may affect the length of any ongoing Unwind Period; accordingly, Counterparty acknowledges that its delivery of such notice must comply with the standards set forth in Section 6(c) above. “Merger Transaction” means any merger, acquisition or similar transaction involving a recapitalization as contemplated by Rule 10b-18(a)(13)(iv) under the Exchange Act. For the avoidance of doubt, a Merger Transaction or the announcement thereof shall not give either party the right to designate an Early Valuation Date for any Transaction and/or to accelerate or preclude an election by Counterparty of Physical Settlement for any Settlement of any Transaction, unless such Merger Transaction or the announcement thereof is also an ISDA Event.

7. Termination on Bankruptcy. The parties hereto agree that, notwithstanding anything to the contrary in the Agreement or the Equity Definitions, each Transaction constitutes a contract to issue a security of Counterparty as contemplated by Section 365(c)(2) of the Bankruptcy Code and that a Transaction and the obligations and rights of Counterparty and Dealer (except forany liability as a result of breach of any of the representations or warranties provided by Counterparty in Section 4 or Section 5 above) shall immediately terminate, without the necessity of any notice, payment (whether directly, by netting or otherwise) or other action by Counterparty or Dealer, if, on or prior to the final Physical Settlement Date, Cash Settlement Payment Date or Net Share Settlement Date, as the case may be, for such Transaction an Insolvency Filing occurs or any other proceeding commences with respect to Counterparty under the Bankruptcy Code (a “Bankruptcy Termination Event”).

8. Additional Provisions.

(a) Dealer acknowledges and agrees that Counterparty’s obligations under the Transactions are not secured by any collateral and that neither this Master Confirmation nor any Supplemental Confirmation is intended to convey to Dealer rights with respect to the transactions contemplated hereby and by any Supplemental Confirmation that are senior to the claims of common stockholders in any U.S. bankruptcy proceedings of Counterparty; provided that nothing herein shall limit or shall be deemed to limit Dealer’s right to pursue remedies in the event of a breach by Counterparty of its obligations and agreements with respect to this Master Confirmation, any Supplemental Confirmation or the Agreement; provided further that nothing herein shall limit or shall be deemed to limit Dealer’s rights in respect of any transaction other than the Transactions.

(b) [Reserved]

(c) The parties hereto intend for:

(i) each Transaction to be a “securities contract” as defined in Section 741(7) of the Bankruptcy Code, and the parties hereto to be entitled to the protections afforded by, among other Sections, Sections 362(b)(6), 362(b)(27), 362(o), 546(e), 546(j), 555 and 561 of the Bankruptcy Code;

(ii) the rights given to Dealer pursuant to “Early Valuation” in Section 2 above to constitute “contractual rights” to cause the liquidation of a “securities contract” and to set off mutual debts and claims in connection with a “securities contract”, as such terms are used in Sections 555 and 362(b)(6) of the BankruptcyCode;

(iii) any cash, securities or other property provided as performance assurance, credit support or collateral with respect to the Transactions to constitute “margin payments” and “transfers” under a “securities contract” as defined in the Bankruptcy Code;

(iv) all payments for, under or in connection with the Transactions, all payments for Shares and the transfer of Shares to constitute “settlement payments” and “transfers” under a “securities contract” as defined in the Bankruptcy Code; and

(v) any or all obligations that either party has with respect to this Master Confirmation, any Supplemental Confirmation or the Agreement to constitute property held by or due from such party to margin, guaranty or settle obligations of the other party with respect to the transactions under the Agreement (including the Transactions) or any other agreement between such parties.

(d) Notwithstanding any other provision of the Agreement, this Master Confirmation or any Supplemental Confirmation, in no event will Counterparty be required to deliver in the aggregate in respect of all Settlement Dates, Net Share Settlement Dates or other dates on which Shares are delivered in respect of any amount owed under any Transaction a number of Shares greater than 1.25 times the Number of Shares for such Transaction as of the Trade Date for such Transaction (the “Capped Number”). The Capped Number shall be subject to adjustment only on account of (x) Potential Adjustment Events of the type specified in (1) Sections 11.2(e)(i) through (vi) of the Equity Definitions or (2) Section 11.2 (e)(vii) of the Equity Definitions so long as, in the case of this sub-clause (2), such event is within Issuer’s control, (y)

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Merger Events requiring corporate action of Issuer (or any surviving entity of the Issuer hereunder in connection with any such Merger Event) and (z) announcements with respect to a Merger Event that are not outside Issuer’s control. Counterparty represents and warrants to Dealer (which representation and warranty shall be deemed to be repeated for all Transactions on each day that any Transaction is outstanding) that the aggregate Capped Number across all Transactions hereunder is equal to or less than the number of authorized but unissued Shares that are not reserved for future issuance in connection with transactions in the Shares (other than the Transactions) on the date of the determination of such aggregated Capped Number. In the event Counterparty shall not have delivered the full number of Shares otherwise deliverable under any Transaction as a result of this Section 8(d) (the resulting deficit for such Transaction, the “Deficit Shares”), Counterparty shall be continually obligated to deliver Shares, from time to time until the full number of Deficit Shares have been delivered pursuant to this paragraph, on a pro rata basis across all Transactions hereunder, when, and to the extent that, (A) Shares are repurchased, acquired or otherwise received by Counterparty or any of its subsidiaries after the date hereof (whether or not in exchange for cash, fair value or any other consideration), (B) authorized and unissued Shares reserved for issuance in respect of other transactions prior to such date which prior to the relevant date become no longer so reserved and (C) Counterparty additionally authorizes any unissued Shares that are not reserved for transactions other than the Transactions (such events as set forth in clauses (A), (B) and (C) above, collectively, the “Share Issuance Events”). Counterparty shall promptly notify Dealer of the occurrence of any of the Share Issuance Events (including the number of Shares subject to clause (A), (B) or (C) and the corresponding number of Shares to be delivered for each Transaction) and, as promptly as reasonably practicable, deliver such Shares thereafter. Counterparty shall not, until Counterparty’s obligations under the Transactions have been satisfied in full, use any Shares that become available for potential delivery to Dealer as a result of any Share Issuance Event for the settlement or satisfaction of any transaction or obligation other than the Transactions or reserve any such Shares for future issuance for any purpose other than to satisfy Counterparty’s obligations to Dealer under the Transactions.

(e) The parties intend for this Master Confirmation and each Supplemental Confirmation to constitute a “Contract” as described in the letter dated October 6, 2003 submitted on behalf of Goldman, Sachs & Co. to Paula Dubberly of the staff of the Securities and Exchange Commission (the “Staff”) to which the Staff responded in an interpretive letter dated October 9, 2003.

(f) The parties intend for each Transaction (taking into account purchases of Shares in connection with any Cash Settlement or Net Share Settlement of any Transaction) to comply with the requirements of Rule 10b5-1(c)(1)(i)(A) under the Exchange Act and for this Master Confirmation and each Supplemental Confirmation to constitute a binding contract or instruction satisfying the requirements of 10b5-1(c) and to be interpreted to comply with the requirements of Rule 10b5-1(c).

(g) Notwithstanding any provisions of the Agreement, all communications relating to the Transactions or the Agreement shall be transmitted exclusively through Dealer at the notice address specified under “Dealer’s Contact Details for Purpose of Giving Notice” in Section 2 of this Master Confirmation.

(h) Counterparty acknowledges that:

(i) during the term of the Transactions, Dealer and its affiliates may buy or sell Shares or other securities or buy or sell options or futures contracts or enter into swaps or other derivative securities in order to establish, adjust or unwind its commercially reasonable hedge position with respect to the Transactions;

(ii) Dealer and its affiliates may also be active in the market for the Shares and derivatives linked to the Shares other than in connection with commercially reasonable hedging activities in relation to the Transactions, including acting as agent or as principal and for its own account or on behalf of customers;

(iii) Dealer shall make its own determination as to whether, when or in what manner any hedging or market activities in Counterparty’s securities shall be conducted and shall do so in a manner that it deems appropriate in its commercially reasonable discretion to hedge its price and market risk with respect to the Forward Price and the Settlement Price for each Transaction; provided, that if the provisions of this Transaction require adjustment to reflect the economic effect on an adjustment event on Dealer’s hedge, such adjustment shall be made as if and to the extent Dealer had a commercially reasonable hedge;

(iv) any market activities of Dealer and its affiliates with respect to the Shares may affect the market price and volatility of the Shares, as well as the Forward Price and the Settlement Price for each Transaction, each in a manner that may be adverse to Counterparty; and

(v) each Transaction is a derivatives transaction; Dealer may purchase or sell shares for its own account at an average price that may be greater than, or less than, the price received by Counterparty under the terms of the relevant Transaction.

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(i) Counterparty and Dealer agree and acknowledge that (A) the Transactions contemplated by this Master Confirmation will be entered into in reliance on the fact that this Master Confirmation and each Supplemental Confirmation hereto form a single agreement between Counterparty and Dealer, and Dealer would not otherwise enter into such Transactions; (B) this Master Confirmation, together with each Supplemental Confirmation hereto, is a “qualified financial contract,” as such term is defined in Section 5-701(b)(2) of the General Obligations Law; (C) each Supplemental Confirmation hereto, regardless of whether transmitted electronically or otherwise, constitutes a “confirmation in writing sufficient to indicate that a contract has been made between the parties” hereto, as set forth in Section 5-701(b)(3)(b) of the General Obligations Law; and (D) this Master Confirmation and each Supplemental Confirmation hereto constitute a prior “written contract,” as set forth in Section 5-701(b)(1)(b) of the General Obligations Law, and each party hereto intends and agrees to be bound by this Master Confirmation and such Supplemental Confirmation.

(j) Counterparty and Dealer agree that, upon the execution and delivery of any Supplemental Confirmation relating to a Transaction by Counterparty, each of the representations, warranties, covenants, agreements and other provisions of this Master Confirmation and the Supplemental Confirmation for such Transaction (including, without limitation, Dealer’s right to designate an Early Valuation Date in respect of such Transaction pursuant to the provisions opposite the caption “Early Valuation” in Section 2 and the termination of such Transaction following a Bankruptcy Termination Event as described in Section 7) shall govern, and be applicable to, such Transaction as of the first Trading Day of the Forward Hedge Selling Period for such Transaction as if the Trade Date for such Transaction were such first Trading Day.

9. Indemnification. Counterparty agrees to indemnify and hold harmless Dealer, its affiliates and their respective directors, officers, employees, and controlling persons (Dealer and each such person being an “Indemnified Party”) from and against any and all losses, claims, damages and liabilities (or actions in respect thereof), joint or several, incurred by or asserted against such Indemnified Party for the violation of federal or state securities law and which arise out of, are in connection with, or relate to, any breach of any covenant or representation made by the Counterparty in this Master Confirmation and any Supplemental Confirmation or the performance by Counterparty of its obligations under the Transactions. In addition, Counterparty will reimburse any Indemnified Party for all reasonable expenses (including reasonable counsel fees and expenses) as they are incurred in connection with the investigation of, preparation for or defense or settlement of any pending or threatened claim or any action, suit or proceeding arising therefrom, whether or not such Indemnified Party is a party thereto and whether or not such claim, action, suit or proceeding is initiated or brought by or on behalf of Counterparty. Counterparty will not be liable under the foregoing indemnification provision to the extent that any loss, claim, damage, liability or expense is found in a nonappealable judgment by a court of competent jurisdiction to have resulted from Dealer’s willful misconduct, gross negligence or bad faith in performing the services that are subject of the Transactions. If for any reason the foregoing indemnification is unavailable to any Indemnified Party or insufficient to hold harmless any Indemnified Party, then Counterparty shall contribute, to the maximum extent permitted by law, to the amount paid or payable by the Indemnified Party as a result of such loss, claim, damage or liability. Counterparty also agrees that no Indemnified Party shall have any liability to Counterparty or any person asserting claims on behalf of or in right of Counterparty in connection with or as a result of any matter referred to in this Master Confirmation and any Supplemental Confirmation except to the extent that any losses, claims, damages, liabilities or expenses incurred by Counterparty result from the material breach of any covenant or representation made by Dealer in this Master Confirmation or any Supplemental Confirmation or the Agreement or any willful misconduct, fraud or bad faith of the Indemnified Party. The provisions of this Section 9 shall survive the completion of the Transactions contemplated by this Master Confirmation and any Supplemental Confirmation and any assignment and/or delegation of the Transactions made pursuant to the Agreement, this Master Confirmation or any Supplemental Confirmation shall inure to the benefit of any permitted assignee of Dealer. For the avoidance of doubt, any payments due as a result of this provision may not be used to set off any obligation of Dealer upon settlement of the Transactions.

10. Beneficial Ownership. Notwithstanding anything to the contrary in the Agreement, this Master Confirmation or any Supplemental Confirmation, in no event shall Dealer be entitled to receive, or be deemed to receive, or have the “right to acquire” (within the meaning of NYSE Rule 312.04(g)) Shares to the extent that, upon such receipt of such Shares, (i) the “beneficial ownership” (within the meaning of Section 13 of the Exchange Act and the rules promulgated thereunder) of Shares by Dealer, any of its affiliates’ business units subject to aggregation with Dealer for purposes of the “beneficial ownership” test under Section 13 of the Exchange Act and all persons who may form a “group” (within the meaning of Rule 13d-5(b)(1) under the Exchange Act) with Dealer with respect to “beneficial ownership” of any Shares (collectively, “Dealer Group”) would be equal to or greater than the lesser of (x) 4.9% of the outstanding Shares (such condition, an “Excess Section 13 Ownership Position”), and (y) 4.9% of the outstanding Shares as of the Trade Date for any Transaction (such number of Shares, the “Threshold Number of Shares” and such condition, the “Excess NYSE Ownership Position”) or (ii) Dealer, Dealer Group or any person whose ownership position would be aggregated with that of Dealer or Dealer Group (Dealer, Dealer Group or any such person, a “Dealer Person”) under Section 203 of the Delaware General Corporation Law or any state or federal bank holding company or banking laws, or any federal, state or local laws,

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regulations or regulatory orders applicable to ownership of Shares (“Applicable Laws”), would own, beneficially own, constructively own, control, hold the power to vote or otherwise meet a relevant definition of ownership in excess of a number of Shares equal to (x) the lesser of (A) the maximum number of Shares that would be permitted under Applicable Laws and (B) the number of Shares that would give rise to reporting or registration obligations or other requirements (including obtaining prior approval by a state or federal regulator) of a Dealer Person under Applicable Laws and with respect to which such requirements have not been met or the relevant approval has not been received or that would give rise to any consequences under the constitutive documents of Counterparty or any contract or agreement to which Counterparty is a party, in each case minus (y) 1% of the number of Shares outstanding on the date of determination (such condition described in clause (ii), an “Excess Regulatory Ownership Position”). If any delivery owed to Dealer under any Transaction is not made, in whole or in part, as a result of this provision, (i) Counterparty’s obligation to make such delivery shall not be extinguished and Counterparty shall make such delivery as promptly as practicable after, but in no event later than one Exchange Business Day after, Dealer gives notice to Counterparty that such delivery would not result in Dealer Group directly or indirectly so beneficially owning in excess of the lesser of (A) 4.9% of the outstanding Shares and (B) the Threshold Number of Shares or (y) the occurrence of an Excess Regulatory Ownership Position and (ii) if such delivery relates to a Physical Settlement of any Transaction, notwithstanding anything to the contrary herein, Dealer shall not be obligated to satisfy the portion of its payment obligation with respect to such Transaction corresponding to any Shares required to be so delivered until the date Counterparty makes such delivery.

11. Non-Confidentiality. The parties hereby agree that (i) effective from the date of commencement of discussions concerning the Transactions, Counterparty and each of its employees, representatives, or other agents may disclose to any and all persons, without limitation of any kind, the tax treatment and tax structure of the Transactions and all materials of any kind, including opinions or other tax analyses, provided by Dealer and its affiliates to Counterparty relating to such tax treatment and tax structure; provided that the foregoing does not constitute an authorization to disclose the identity of Dealer or its affiliates, agents or advisers, or, except to the extent relating to such tax structure or tax treatment, any specific pricing terms or commercial or financial information, and (ii) Dealer does not assert any claim of proprietary ownership in respect of any description contained herein or therein relating to the use of any entities, plans or arrangements to give rise to a particular United States federal income tax treatment for Counterparty.

12. Restricted Shares. If Counterparty is unable to comply with the covenant of Counterparty contained in Section 6(a)(iii) above because of a change in law or a change in the policy of the Securities and Exchange Commission or its staff, or Dealer otherwise determines in its reasonable opinion based on advice of counsel that any Shares to be delivered to Dealer by Counterparty under any Transaction may not be freely returned by Dealer to securities lenders as described in the covenant of Counterparty contained in Section 6(a)(iii) above, then delivery of any such Settlement Shares (the “Unregistered Settlement Shares”) shall be effected pursuant to Annex A hereto, unless waived by Dealer.

13. Use of Shares. Dealer acknowledges and agrees that, except in the case of a Private Placement Settlement (as defined in Annex A hereto), Dealer shall use any Shares delivered by Counterparty to Dealer or an affiliate on any Settlement Date to return to securities lenders to close out borrowings created by Dealer in connection with its hedging activities related to exposure under the Transactions or otherwise in compliance with applicable law.

14. Rule 10b-18. In connection with bids and purchases of Shares in connection with any Net Share Settlement or Cash Settlement of any Transaction, Dealer shall use commercially reasonable efforts to conduct its activities, or cause its affiliates to conduct their activities, in a manner consistent with the requirements of paragraphs (b)(2), (b)(3) and (b)(4) of the safe harbor provided by Rule 10b-18 under the Exchange Act, as if such provisions were applicable to such purchases and taking into account any applicable Securities and Exchange Commission no-action letters as appropriate, and subject to any delays between the execution and reporting of a trade of the Shares on the Exchange and other circumstances beyond Dealer’s control; provided further that, without limiting the generality of this Section 14, Dealer shall not be responsible for any failure to comply with Rule 10b-18(b)(3) to the extent any transaction that was executed (or deemed to be executed) by or on behalf of Counterparty or an “affiliated purchaser” (as defined under Rule 10b-18) pursuant to a separate agreement is not deemed to be an “independent bid” or an “independent transaction” for purposes of Rule 10b-18(b)(3).

15. Governing Law. Notwithstanding anything to the contrary in the Agreement, the Agreement, this Master Confirmation, any Supplemental Confirmation and all matters arising in connection with the Agreement this Master Confirmation and any Supplemental Confirmation shall be governed by, and construed and enforced in accordance with, the laws of the State of New York (without reference to its choice of laws doctrine other than Title 14 of Article 5 of the New York General Obligations Law).

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16. Set-Off.

(a) The parties agree that upon the occurrence of an Event of Default or Termination Event with respect to a party who is the Defaulting Party or the Affected Party (“X”), the other party (“Y”) will have the right (but not be obliged) without prior notice to X or any other person to set-off or apply any obligation of X owed to Y (whether or not matured or contingent and whether or not arising under the Agreement, and regardless of the currency, place of payment or booking office of the obligation) against any obligation of Y owed to X (whether or not matured or contingent and whether or not arising under the Agreement, and regardless of the currency, place of payment or booking office of the obligation). Y will give notice to the other party of any set-off effected under this Section 16.

Amounts (or the relevant portion of such amounts) subject to set-off may be converted by Y into the Termination Currency at the rate of exchange at which such party would be able, acting in a reasonable manner and in good faith, to purchase the relevant amount of such currency. If any obligation is unascertained, Y may in good faith estimate that obligation and set-off in respect of the estimate, subject to the relevant party accounting to the other when the obligation is ascertained. Nothing in this Section 16 shall be effective to create a charge or other security interest. This Section 16 shall be without prejudice and in addition to any right of set-off, combination of accounts, lien or other right to which any party is at any time otherwise entitled (whether by operation of law, contract or otherwise).

(b) Notwithstanding anything to the contrary in the foregoing, Dealer agrees not to set off or net amounts due from Counterparty with respect to any Transaction against amounts due from Dealer to Counterparty with respect to contracts or instruments that are not Equity Contracts. “Equity Contract” means any transaction or instrument that does not convey to Dealer rights, or the ability to assert claims, that are senior to the rights and claims of common stockholders in the event of Counterparty’s bankruptcy and would be classified as equity according to generally accepted accounting principles in the United States.

17. Staggered Settlement. Notwithstanding anything to the contrary herein, Dealer may, by prior notice to Counterparty, satisfy its obligation to deliver any Shares or other securities on any date due (an “Original Delivery Date”) by making separate deliveries of Shares or such securities, as the case may be, at more than one time on or prior to such Original Delivery Date, so long as the aggregate number of Shares and other securities so delivered on or prior to such Original Delivery Date is equal to the number required to be delivered on such Original Delivery Date.

18. Waiver of Trial by Jury. EACH OF COUNTERPARTY AND DEALER HEREBY IRREVOCABLY WAIVES (ON ITS OWN BEHALF AND, TO THE EXTENT PERMITTED BY APPLICABLE LAW, ON BEHALF OF ITS STOCKHOLDERS) ALL RIGHT TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED ON CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR RELATING TO THE TRANSACTION OR THE ACTIONS OF DEALER OR ITS AFFILIATES IN THE NEGOTIATION, PERFORMANCE OR ENFORCEMENT HEREOF.

19. Jurisdiction. THE PARTIES HERETO IRREVOCABLY SUBMIT TO THE EXCLUSIVE JURISDICTION OF THE COURTS OF THE STATE OF NEW YORK AND THE UNITED STATES COURT FOR THE SOUTHERN DISTRICT OF NEW YORK IN CONNECTION WITH ALL MATTERS RELATING HERETO AND WAIVE ANY OBJECTION TO THE LAYING OF VENUE IN, AND ANY CLAIM OF INCONVENIENT FORUM WITH RESPECT TO, THESE COURTS. NOTHING IN THIS PROVISION SHALL PROHIBIT A PARTY FROM BRINGING AN ACTION TO ENFORCE A MONEY JUDGMENT IN ANY OTHER JURISDICTION.

20. Counterparts. This Master Confirmation may be executed in any number of counterparts, all of which shall constitute one and the same instrument, and any party hereto may execute this Master Confirmation by signing and delivering one or more counterparts.

21. Delivery of Cash. For the avoidance of doubt, nothing in this Master Confirmation or any Supplemental Confirmation shall be interpreted as requiring Counterparty to deliver cash or other assets in respect of the settlement of the Transactions, except in circumstances where the required cash or other asset settlement thereof is permitted for classification of the contract as equity by ASC 815-40, Derivatives and Hedging — Contracts in Entity’s Own Equity, as in effect on the date hereof.

22. Adjustments. For the avoidance of doubt, whenever the Calculation Agent, the Hedging Party or the Determining Party is called upon to make an adjustment pursuant to the terms of this Master Confirmation, any Supplemental Confirmation or the Equity Definitions to take into account the effect of an event, the Calculation Agent, the Hedging Party or the Determining Party, as applicable, shall make such adjustment by reference to the effect of such event on the Hedging Party, assuming that the Hedging Party maintains a commercially reasonable hedge position at the time of the event.

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23. Other Forward Transactions. Counterparty agrees that (x) it shall not enter into, or permit to exist, any Transaction hereunder if Counterparty is party to any other issuer forward sale or similar transaction (including, without limitation, any “Transaction” under (as and defined under) any substantially identical master forward confirmation) with any financial institution other than Dealer (an “Other Forward Transaction”) and (y) Counterparty shall not enter into, or permit to exist, any Other Forward Transaction at any time at which Counterparty is party to a Transaction hereunder, in each case unless no part of the Forward Hedge Selling Period under any Transaction hereunder occurs during any part of the corresponding period under such Other Forward Transaction and no Unwind Date under any Transaction hereunder occurs on a corresponding date under such Other Forward Transaction. For the avoidance of doubt, the foregoing prohibitions shall not apply during any time at which this Master Confirmation remains in effect but no Transaction evidenced by a Supplemental Confirmation hereunder shall exist.

24. Review of Confirmation. Counterparty hereby agrees (a) to check this Master Confirmation carefully and promptly upon receipt so that errors or discrepancies can be promptly identified and rectified and (b) to confirm that the foregoing (in the exact form provided by Dealer) correctly sets forth the terms of the agreement between Dealer and Counterparty hereunder, by manually signing this Master Confirmation or this page hereof as evidence of agreement to such terms and providing the other information requested herein and immediately returning an executed copy to us.

25. Counterparty Payee Tax Representations. For the purposes of Section 3(f) of the Agreement, Counterparty represents that:

26. Tax Forms. For the purpose of Section 4(a)(i) or 4(a)(ii) of the Agreement, Counterparty agrees to deliver the following documents (each in form and substance reasonably satisfactory to Dealer), as applicable:

27. Payer Tax Representation. Dealer and Counterparty each make the following representation:

It is not required by any applicable law, as modified by the practice of any relevant governmental revenue authority, of any Relevant Jurisdiction to make any deduction or withholding for or on account of any Tax from any payment (other than interest under Section 9(h) of this Agreement) to be made by it to the other party under this Agreement. In making this representation, it may rely on (i) the accuracy of any representations made by the other party pursuant to Section 3(f) of this Agreement, (ii) the satisfaction of the agreement contained in Section 4(a)(i) or 4(a)(iii) of this Agreement and the accuracy and effectiveness of any document provided by the other party pursuant to Section 4(a)(i) or 4(a)(iii) of this Agreement and (iii) the satisfaction of the agreement of the other party contained in Section 4(d) of this Agreement, except that it will not be a breach of this representation where reliance is placed on clause (ii) above and the other party does not deliver a form or document under Section 4(a)(iii) by reason of material prejudice to its legal or commercial position.

28. Other Provisions.

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Signature Page to the Master Confirmation

Signature Page to the Master Confirmation

ANNEX A

PRIVATE PLACEMENT PROCEDURES

If Counterparty delivers Unregistered Settlement Shares pursuant to Section 12 above (a “Private Placement Settlement”), then:

(a) all Unregistered Settlement Shares shall be delivered to Dealer (or any affiliate of Dealer designated by Dealer) pursuant to the exemption from the registration requirements of the Securities Act provided by Section 4(a)(2) thereof;

(b) as of or prior to the date of delivery, Dealer and any potential purchaser of any such shares from Dealer (or any affiliate of Dealer designated by Dealer) identified by Dealer shall be afforded a commercially reasonable opportunity to conduct a due diligence investigation with respect to Counterparty customary in scope for private placements of equity securities of similar size (including, without limitation, the right to have made available to them for inspection all financial and other records, pertinent corporate documents and other information reasonably requested by them); provided that prior to receiving or being granted access to any such information, Dealer, such affiliate of Dealer or such potential purchaser, as the case may be, may be required by Counterparty to enter into a customary nondisclosure agreement with Counterparty in respect of any such due diligence investigation;

(c) as of the date of delivery, Counterparty shall enter into an agreement (a “Private Placement Agreement”) with Dealer (or any affiliate of Dealer designated by Dealer) in connection with the private placement of such shares by Counterparty to Dealer (or any such affiliate) and the private resale of such shares by Dealer (or any such affiliate), substantially similar to private placement purchase agreements customary for private placements of equity securities of similar size, in form and substance commercially reasonably satisfactory to Dealer, which Private Placement Agreement shall include, without limitation, provisions substantially similar to those contained in such private placement purchase agreements relating, without limitation, to the indemnification of, and contribution in connection with the liability of, Dealer and its affiliates and obligations to use commercially reasonable efforts to obtain customary opinions, accountants’ comfort letters and lawyers’ negative assurance letters, and shall provide for the payment by Counterparty of all commercially reasonable fees and expenses in connection with such resale, including all commercially reasonable fees and expenses of counsel for Dealer, and shall contain representations, warranties, covenants and agreements of Counterparty reasonably necessary or advisable to establish and maintain the availability of an exemption from the registration requirements of the Securities Act for such resales; and

(d) in connection with the private placement of such shares by Counterparty to Dealer (or any such affiliate) and the private resale of such shares by Dealer (or any such affiliate), Counterparty shall, if so requested by Dealer, prepare, in cooperation with Dealer, a private placement memorandum in form and substance reasonably satisfactory to Dealer.

In the case of a Private Placement Settlement, Dealer shall, in its good faith discretion, adjust the amount of Unregistered Settlement Shares to be delivered to Dealer hereunder in a commercially reasonable manner to reflect the fact that such Unregistered Settlement Shares may not be freely returned to securities lenders by Dealer and may only be saleable by Dealer at a discount to reflect the lack of liquidity in Unregistered Settlement Shares.

If Counterparty delivers any Unregistered Settlement Shares in respect of a Transaction, Counterparty agrees that (i) such Shares may be transferred by and among Dealer and its affiliates and (ii) after the minimum “holding period” within the meaning of Rule 144(d) under the Securities Act has elapsed after the applicable Settlement Date, Counterparty shall promptly remove, or cause the transfer agent for the Shares to remove, any legends referring to any transfer restrictions from such Shares upon delivery by Dealer (or such affiliate of Dealer) to Counterparty or such transfer agent of seller’s and broker’s representation letters customarily delivered by Dealer or its affiliates in connection with resales of restricted securities pursuant to Rule 144 under the Securities Act, each without any further requirement for the delivery of any certificate, consent, agreement, opinion of counsel, notice or any other document, any transfer tax stamps or payment of any other amount or any other action by Dealer (or such affiliate of Dealer).

Annex A-1

EXHIBIT A

SUPPLEMENTAL CONFIRMATION

Dear Sir(s):

The purpose of this Supplemental Confirmation is to confirm the terms and conditions of the Transaction entered into between [Dealer] (“Dealer”) and Atmos Energy Corporation (“Counterparty”) (together, the “Contracting Parties”) on the Trade Date specified below. This Supplemental Confirmation is a binding contract between Dealer and Counterparty as of the relevant Trade Date for the Transaction referenced below.

Exhibit A-1

Signature Page to the Supplemental Confirmation

Schedule I

FORWARD PRICE REDUCTION AMOUNTS

REGULAR DIVIDEND AMOUNTS

Schedule I-1

EXHIBIT B

HEDGE COMPLETION NOTICE

Dear Sir(s):

This Hedge Completion Notice (“Hedge Completion Notice”) is furnished by [Dealer] (“Dealer”) to Atmos Energy Corporation (“Counterparty”) (together, the “Contracting Parties”) in accordance with the Supplemental Confirmation dated [ ], 20[ ] (the “Supplemental Confirmation”) between the Contracting Parties. This Hedge Completion Notice specifies the terms required by the Supplemental Confirmation and supplements, forms a part of, and is subject to the Supplemental Confirmation, and Master Confirmation dated as of [DATE] (the “Master Confirmation”), between the Contracting Parties, as each may be amended or supplemented from time to time.

The terms required by the Supplemental Confirmation are as follows:

Exhibit B-1