ONEOK, INC. EQUITY COMPENSATION PLAN Amended and Restated

Exhibit 4.1

ONEOK, INC.

EQUITY COMPENSATION PLAN

Amended and Restated February 21, 2008

1.1 Purposes . The purposes of this Plan are (a) to provide competitive incentives that will enable the Company to attract, retain, motivate, and reward eligible Employees and Non-Employee Directors of the Company, and (b) to give the Company’s eligible Employees and Non-Employee Directors an interest parallel to the interests of the Company’s shareholders generally.

1.2 Duration of Plan . The date of adoption and term of the Plan are as follows:

(a) The Plan was initially adopted and effective on February 17, 2005, the date of its first adoption and approval by the Board of Directors, such adoption of the Plan having been approved by the shareholders of the Company within one (1) year of that date, on May 19, 2005. The term of the Plan as so initially adopted and approved was until a termination date of February 17, 2015, or until sooner terminated by the Board of Directors.

(b) The Plan, as amended and restated in and by this instrument, is effective on an Effective Date of February 21, 2008, the date of its adoption and approval by the Board of Directors, provided that the shareholders of the Company thereafter approve it within one (1) year of that date. If the Plan, as so amended and restated, is so approved by the shareholders of the Company, it shall have an extended term and shall terminate on a termination date of February 21, 2018, or until sooner terminated by the Board of Directors.

(c) If the Plan, as so amended and restated in and by this instrument, is not so approved by the shareholders of the Company, the amendments thereto and this instrument shall not become effective and shall be of no force and effect, and the Plan shall remain in effect in accordance with its written terms and provisions as initially adopted and approved.

(d) The Plan shall remain in effect until its termination date, or until the Plan is sooner terminated by the Board of Directors, and upon its termination shall continue to be administered thereafter with respect to any Stock Incentive granted prior to the date of such termination.

(e) In no event shall a Stock Incentive be granted under the Plan more than ten (10) years from February 21, 2008, the date the Plan, as amended and restated in and by this instrument, is adopted.

Unless otherwise required by the context, the following terms, when and wherever used in this Plan, shall have the meanings set forth in this Section 2.

2.1 “Beneficiary” means a person or entity (including a trust or estate), designated in writing by a Participant on such forms and in accordance with such terms and conditions as the Committee may prescribe, to whom the Participant’s rights under the Plan shall pass in the event of the death of the Participant.

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2.2 “Board” or a “Board of Directors” means the Board of Directors of the Company, as constituted from time to time.

2.3 A “Change in Control” shall mean the occurrence of any of the following:

(a) An acquisition (other than directly from the Company) of any voting securities of the Company (the “Voting Securities”) by any “Person” (as the term person is used for purposes of Section 13(d) or 14(d) of the Exchange Act), immediately after which such Person has “Beneficial Ownership” (within the meaning of Rule 13d-3 promulgated under the Exchange Act) of twenty percent (20%) or more of the then outstanding Shares or the combined voting power of the Company’s then outstanding Voting Securities; provided, however, in determining whether a Change in Control has occurred pursuant to this Section 2(c), Shares or Voting Securities which are acquired in a “Non-Control Acquisition” (as hereinafter defined) shall not constitute an acquisition which would cause a Change in Control. A “Non-Control Acquisition” shall mean an acquisition by (i) an employee benefit plan (or a trust forming a part thereof) maintained by (A) the Company or (B) any company or other Person of which a majority of its voting power or its voting equity securities or equity interest is owned or controlled, directly or indirectly, by the Company (for purposes of this definition, a “Related Entity”), (ii) the Company or any Related Entity, or (iii) any Person in connection with a “Non-Control Transaction” (as hereinafter defined);

(b) The individuals who, as of February 15, 2001, are members of the Board of Directors (the “Incumbent Board”), cease for any reason to constitute at least a majority of the members of the Board of Directors; or, following a Merger which results in a Parent Company, the board of directors of the ultimate Parent Company; provided, however, that if the election, or nomination for election by the Company’s common stockholders, of any new director was approved by a vote of at least two-thirds of the Incumbent Board, such new director shall, for purposes of this Plan, be considered as a member of the Incumbent Board; provided further, however, that no individual shall be considered a member of the Incumbent Board if such individual initially assumed office as a result of either an actual or threatened “Election Contest” (as described in Rule 14a-11 promulgated under the Exchange Act) or other actual or threatened solicitation of proxies or consents by or on behalf of a Person other than the Board of Directors (a “Proxy Contest”), including by reason of any agreement intended to avoid or settle any Election Contest or Proxy Contest; or

(c) The consummation of:

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Notwithstanding the foregoing, a Change in Control shall not be deemed to occur solely because any Person (the “Subject Person”) acquired Beneficial Ownership of more than the permitted amount of the then outstanding Shares or Voting Securities if: (1) such acquisition occurs as a result of the acquisition of Shares or Voting Securities by the Company which, by reducing the number of Shares or Voting Securities then outstanding, increases the proportional number of shares Beneficially Owned by the Subject Person, provided that if a Change in Control would occur (but for the operation of this subparagraph) as a result of the acquisition of Shares or Voting Securities by the Company, and after such share acquisition by the Company, the Subject Person becomes the Beneficial Owner of any additional Shares or Voting Securities which increases the percentage of the then outstanding Shares or Voting Securities Beneficially Owned by the Subject Person, then a Change in Control shall occur, or (2) (A) within five business days after a Change in Control would have occurred (but for the operation of this subparagraph), or if the Subject Person acquired Beneficial Ownership of twenty percent (20%) or more of the then outstanding Shares or the combined voting power of the Company’s then

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outstanding Voting Securities inadvertently, then after the Subject Person discovers or is notified by the Company that such acquisition would have triggered a Change in Control (but for the operation of this subparagraph), the Subject Person notifies the Board of Directors that it did so inadvertently, and (B) within two business days after such notification, the Subject Person divests itself of a sufficient number of Shares or Voting Securities so that the Subject Person is the Beneficial Owner of less than twenty percent (20%) of the then outstanding Shares or the combined voting power of the Company’s then outstanding Voting Securities.

Notwithstanding anything in this Plan to the contrary, if an eligible Employee’s employment is terminated by the Company without Just Cause prior to the date of a Change in Control but the eligible Employee reasonably demonstrates that the termination (1) was at the request of a third party who has indicated an intention or taken steps reasonably calculated to effect a Change in Control or (2) otherwise arose in connection with, or in anticipation of, a Change in Control which has been threatened or proposed, such termination shall be deemed to have occurred after a Change in Control for purposes of this Plan, provided a Change in Control shall actually have occurred.

2.4 “Code” means the Internal Revenue Code of 1986, as amended and in effect from time to time. References to a particular section of the Code shall include references to any related Treasury Regulations and to successor provisions.

2.5 “Committee” means the Committee appointed by the Board of Directors to administer the Plan pursuant to the provisions of section 12.1 below.

2.6 “Common Stock” means common stock, $0.01 par value, of the Company.

2.7 “Company” means ONEOK, Inc., an Oklahoma corporation, its successors and assigns, or any division or Subsidiary thereof.

2.8 “Director Fees” means all compensation and fees paid to a Non-Employee Director by the Company for his or her services as a member of the Board of Directors.

2.9 “Director Stock Award” means an award of ONEOK, Inc. Common Stock granted to a Non-Employee Director.

2.10 “Effective Date” means February 21, 2008, the date the Plan, as amended and restated in and by this instrument, is adopted, as provided in Section 1.2, above.

2.11 “Employee” means an employee of the Company, including an officer or director who is such an employee.

2.12 “Exchange Act” means the Securities Exchange Act of 1934, as amended from time to time.

2.13 “Fair Market Value” on a particular date means the average of the high and low sale prices of a share of Common Stock in consolidated trading on the date in question as reported by The Wall Street Journal or another reputable source designated by the Committee; provided that if there were no sales on such date reported as provided above, the respective prices on the most recent

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prior day for which a sale was so reported. In the case of an Incentive Stock Option, if the foregoing method of determining Fair Market Value should be inconsistent with section 422 of the Code, or in the case of any other type of Stock Incentive the foregoing method is determined by the Committee, in its discretion, to not be applicable, a “Fair Market Value” shall be determined by the Committee in a manner consistent with such section of the Code, or in such other manner as the Committee, in its discretion, determines to be appropriate, and shall mean the value as so determined.

2.14 “General Counsel” means the General Counsel of the Company serving from time to time.

2.15 “Incentive Stock Option” means an option, including an Option as the context may require, intended to qualify for the tax treatment applicable to incentive stock options under section 422 of the Code.

2.16 “Just Cause” shall mean the Employee’s conviction in a court of law of a felony, or any crime or offense in a court of law of a felony, or any crime or offense involving misuse or misappropriation of money or property, the Employee’s violation of any covenant, agreement or obligation not to disclose confidential information regarding the business of the Company (or a division or Subsidiary); any violation by the Employee of any covenant not to compete with the Company (or a division or Subsidiary); any act of dishonesty by the Employee which adversely affects the business of the Company (or a division or subsidiary); any willful or intentional act of the Employee which adversely affects the business of, or reflects unfavorably on the reputation of the Company (or a division or Subsidiary); the Employee’s use of alcohol or drugs which interferes with the Employee’s performance of duties as an employee of the Company (or a division or Subsidiary); or the Employee’s failure or refusal to perform the specific directives of the Company’s Board of Directors, or its officers which directives are consistent with the scope and nature of the Employee’s duties and responsibilities with the existence and occurrence of all of such causes to be determined by the Company in its sole discretion; provided, that nothing contained in the foregoing provisions of this paragraph shall be deemed to interfere in any way with the right of the Company (or a division or Subsidiary), which is hereby acknowledged, to terminate the Employee’s employment at any time without cause.

2.17 “Non-Employee Director” means a member of the Board of Directors of the Company who is not an employee of the Company, and who qualifies as a “Non-Employee Director” under the definition of that term in SEC Rule 16b-3.

2.18 “Non-Qualified Performance Stock Incentive” means a Performance Stock Incentive granted under the Plan that is not intended to qualify as qualified performance based compensation under Section 162(m) of the Code, as described in Section 13.9.

2.19 “Non-Statutory Stock Option” means an option, including an Option as the context may require, which is not intended to qualify for the tax treatment applicable to incentive stock options under section 422 of the Code.

2.20 “Option” means an option granted under this Plan to purchase shares of Common Stock. Options may be Incentive Stock Options or Non-Statutory Stock Options.

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2.21 “Participant” means an Employee who the Committee determines is in a position to contribute significantly to the growth and profitability of, or to perform services of major importance to the Company, its divisions and subsidiaries, or Non-Employee Director, who is selected by the Committee to be a Participant in the Plan and to be granted a Stock Incentive under the Plan.

2.22 “Performance Goal” means one or more criteria or standards established by the Committee to determine, in whole or in part, whether a Performance Stock Incentive shall be awarded or earned, which may include the criteria and standards established pursuant to Section 13.9.

2.23 “Performance Period” means the time period designated by the Committee during which Performance Goals must be met.

2.24 “Performance Stock Award” means a Stock Incentive providing for a grant of shares of Common Stock the award or delivery of which is subject to specified Performance Goals.

2.25 “Performance Stock Incentive” means a Stock Incentive, including without limitation, a Performance Stock Award, Performance Unit Award, Restricted Stock Award, or Restricted Unit Award providing for the award, delivery or payment of shares of Common Stock or cash, or a combination of each, that is subject to specified Performance Goals.

2.26 “Performance Unit Award” means a Stock Incentive providing for a grant of a unit or units representing an amount of cash or shares of Common Stock (including a Stock Unit as defined in Section 2.39), or a combination of each, that will be distributed in the future if continued employment and/or other specified Performance Goals or other performance criteria specified by the Committee are attained; and which Performance Goals or other performance criteria may include, without limitation, corporate, divisional or business unit financial or operating performance measures, as more particularly described in Section 13.9; and which other contingencies may include the Participant’s depositing with the Company, acquiring or retaining for stipulated time periods specified amounts of Common Stock; and the amount of Stock Incentive may, but need not be determined by reference to the market value of Common Stock.

2.27 “Plan” means the ONEOK, Inc. Equity Compensation Plan set forth in these pages, as amended from time to time.

2.28 “Plan Year” means the calendar year beginning on January 1 and ending the next December 31.

2.29 “Qualified Performance Stock Incentive” means a Performance Stock Incentive granted under the Plan that is intended to qualify as qualified performance based compensation under Section 162(m) of the Code, as described in Section 13.9.

2.30 “Restricted Stock Award” means shares of Common Stock which are issued or transferred to a Participant under Section 6, below, and which will become free of restrictions specified by the Committee if continued employment and/or Performance Goals or other performance criteria specified by the Committee are attained; and which Performance Goals or other criteria, circumstances or conditions arise, exist or are satisfied; and which may but need not include, without limitation, corporate, divisional or business unit financial or operating performance measures, as more particularly described in Section 13.9.

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2.31 “Restricted Unit Award” means a Stock Incentive providing for a grant of a unit or units representing an amount of cash or shares of Common Stock or a combination of each, which become free of restrictions specified by the Committee if continued employment and/or Performance Goals or other criteria, circumstances or conditions arise, exist or are attained; and which may but need not include, without limitation, corporate, divisional or business unit financial or operating performance measures, as more particularly described in Section 13.9.

2.32 “SEC Rule 16b-3” means Rule 16b-3 of the Securities and Exchange Commission promulgated under the Exchange Act, as such rule or any successor rule may be in effect from time to time.

2.33 “Secretary” means the Secretary of the Company.

2.34 “Section 16 Person” means a person subject to Section 16(b) of the Exchange Act with respect to transactions involving equity securities of the Company.

2.35 “Share” or “shares” means a share or shares of Common Stock, par value $.01 per share of the Company.

2.36 “Stock Appreciation Right” means a right granted to a Participant denominated in shares of Common Stock, to receive, upon exercise of the right (or both the right and a related Option, if applicable in the case of issuance in tandem with an Option), an amount, payable in shares of Common Stock, in cash, or a combination thereof that does not exceed the excess of the Fair Market Value of the share or shares of Common Stock on the date such right is exercised over the base price of such share or shares provided in and for such right on the date such right is granted, as determined by the Committee.

2.37 “Stock Bonus Award” means an amount of cash or shares of Common Stock which is distributed to a Participant or which the Committee agrees to distribute in the future to a Participant in lieu of, or as a supplement to, any other compensation that may have been earned by services rendered prior to the date the distribution is made. Unless otherwise determined by the Committee, the amount of the award shall be determined by reference to the Fair Market Value of Common Stock. Performance Stock Awards, Performance Unit Awards, Restricted Stock Awards and Restricted Unit Awards are specific types of Stock Bonus Awards.

2.38 “Stock Incentive” means an award granted under this Plan in one of the forms provided for in Section 3.

2.39 “Stock Unit” means a unit evidencing the right to receive under certain conditions or in specified circumstances one (1) share of Common Stock or equivalent value, as determined by the Committee.

2.40 “Subsidiary” means a corporation or other form of business association of which shares (or other ownership interest) having more than fifty percent (50%) of the voting power are or in the future become owned or controlled, directly or indirectly, by the Company; provided, however, that in the case of an Incentive Stock Option, the term “Subsidiary” shall mean a Subsidiary (as defined by the preceding clause) which is also a “subsidiary corporation” as defined in Section 424(f) of the Code.

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2.41 “Time-Lapse Restricted Stock Incentive” means a Restricted Stock Award, Restricted Unit Award, or any other Stock Incentive the award of which is based solely on continued employment with the Company for a specified period of time.

3.1 Stock Incentives to Employees/Participants . Subject to the provisions of the Plan, the Committee may at any time, or from time to time, grant Stock Incentives to one or more Employees that the Committee selects to be a Participant in the Plan, which may be (i) Stock Bonus Awards, which may, but need not be Performance Stock Awards, Performance Unit Awards or Restricted Stock Awards, Restricted Unit Awards and/or (ii) Options, which may be Incentive Stock Options or Non-Statutory Stock Options, and/or (ii) Stock Appreciation Rights.

3.2 Non-Employee Director Awards . Subject to the provisions of the Plan, the Committee shall grant Director Stock Awards to Non-Employee Directors in accordance with Section 9 of the Plan. Notwithstanding anything else otherwise expressed or implied in the Plan, no other form of Stock Incentive shall be granted to Non-Employee Directors under the Plan, and in no event shall any grant of an Incentive Stock Option be made to a Non-Employee Director.

3.3 Modifications . After a Stock Incentive has been granted,

(a) the Committee may waive any term or condition thereof that could have been excluded from such Stock Incentive when it was granted, and

(b) with the written consent of the affected Participant, may amend any Stock Incentive after it has been granted to include (or exclude) any provision which could have been included in (or excluded from) such Stock Incentive when it was granted, and no additional consideration need be received by the Company in exchange for such waiver or amendment;

(c) provided, that modification of any Option granted under the Plan shall be subject to the prohibition of repricing of Options stated in Section 7.9.

3.4 Forms of Stock Incentives . A particular form of Stock Incentive may be granted to a Participant either alone or in addition to other Stock Incentives hereunder. The provisions of particular forms of Stock Incentives need not be the same for each Participant.

4.1 Shares Authorized . The maximum number of shares of Common Stock authorized to be issued or transferred pursuant to all Stock Incentives granted under the Plan shall be five million (5,000,000) shares, subject to the provisions governing restoration of shares stated below in Section 4.4 and the provisions for adjustment in Section 11. The maximum number of five million (5,000,000) shares authorized consists of the three million (3,000,000) shares authorized to be issued or transferred on and after the date of initial adoption of the Plan on February 17, 2005, as approved by shareholders of the Company on May 19, 2005, and an additional two million (2,000,000) shares authorized to be issued and transferred by amendment of the Plan and this Section 4.1, adopted and approved by the Board of Directors on February 21, 2008, and approved by shareholders of the Company on May 15, 2008.

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4.2 Grant, Award Limitations . Notwithstanding the foregoing, in addition to the overall maximum limitation in Section 4.1,

(a) The maximum number of shares of Common Stock with respect to which Options or Stock Appreciation Rights may be granted or issued to any one (1) Employee or Participant in any Plan Year is five hundred thousand (500,000);

(b) The maximum number of shares of Common Stock with respect to which Stock Incentives other than Options or Stock Appreciation Rights may be granted or issued to any one (1) Employee or Participant in any Plan Year is five hundred thousand (500,000);

(c) The maximum aggregate number of shares of Common Stock and the maximum dollar amount that may be issued or paid as Performance Stock Incentives to any one (1) Employee or Participant in any Plan Year are five hundred thousand (500,000) shares of Common Stock, and Ten Million Dollars ($10,000,000), respectively;

(d) The maximum aggregate number shares of Common Stock that may be issued under the Plan through the granting of Time-Lapse Restricted Stock Incentives is two million (2,000,000);

(e) The maximum aggregate number of shares of Common Stock that may be issued under the Plan through the granting of Incentive Stock Options is one million seven hundred thousand (1,700,000); and

(f) The exercise of Incentive Stock Options is also subject to the calendar year dollar limitation provided in Section 422(d) of the Code and Section 7.6.

4.3 Source of Shares . Such shares may be authorized but unissued shares of Common Stock, shares of Common Stock held in treasury, whether acquired by the Company specifically for use under this Plan or otherwise, or shares issued or transferred to, or otherwise acquired by, a trust pursuant to Section 13.5, as the Committee may from time to time determine, provided, however, that any shares acquired or held by the Company for the purposes of this Plan shall, unless and until issued or transferred to a trust pursuant to Section 13.5, or to a Participant in accordance with the terms and conditions of a Stock Incentive, be and at all times remain authorized but unissued shares or treasury shares (as the case may be), irrespective of whether such shares are entered in a special account for purposes of this Plan, and shall be available for any corporate purpose.

4.4 Restoration and Retention of Shares . If any shares of Common Stock subject to a Stock Incentive shall not be issued or transferred to a Participant and shall cease to be issuable or transferable to a Participant because of the termination, expiration or cancellation, in whole or in part, of such Stock Incentive or for any other reason, or if any such shares shall, after issuance or transfer, be reacquired by the Company because of the Participant’s failure to comply with the terms and conditions of a Stock Incentive or for any other reason, the shares not so issued or transferred, or the shares so reacquired by the Company, as the case may be, shall no longer be charged against the limitation provided for in Section 4.1 and may be used thereafter for additional Stock Incentives under the Plan; to the extent a Stock Incentive under the Plan is settled or paid in cash, shares subject to such Stock Incentive will not be

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considered to have been issued and will not be applied against the maximum number of shares of Common Stock provided for in Section 4.1. If a Stock Incentive may be settled in shares of Common Stock or cash, such shares shall be deemed issued only when and to the extent that settlement or payment is actually made in shares of Common Stock; to the extent a Stock Incentive is settled or paid in cash, and not shares of Common Stock, any shares previously reserved for issuance or transfer pursuant to such Stock Incentive will again be deemed available for issuance or transfer under the Plan; and the maximum number of shares of Common Stock that may be issued or transferred under the Plan shall be reduced only by the number of shares actually issued and transferred to the Participant. If a Participant pays the purchase price of shares subject to an Option or applicable taxes by surrender