UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D/A (Amendment No. 6)

Under the Securities Exchange Act of 1934

Atlantica Yield plc

(Name of Issuer)

Ordinary Shares, nominal value $0.10 per share

(Title of Class of Securities)

G0751N103

(CUSIP Number)

Jennifer Tindale

Algonquin Power & Utilities Corp.

354 Davis Road, Suite 100

Oakville, ON L6J 2X1

Michael J. Aiello

Sachin Kohli

Weil, Gotshal & Manges LLP

767 5th Avenue

New York, New York 10153

(212) 310-8000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

May 22, 2019

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box.

The information required on this cover page shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Act”), or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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Item 1. Security and Issuer

This Amendment No. 6 (this “Amendment”) to the Schedule 13D filed on March 9, 2018 (the “Original Schedule 13D”), as amended by Amendment No. 1 filed on April 27, 2018, as amended by Amendment No. 2 filed on November 21, 2018, as amended by Amendment No. 3 filed on November 27, 2018, and as amended by Amendment No. 4 filed on February 15, 2019, as amended by Amendment No. 5 filed on May 13, 2019 filed with the Securities and Exchange Commission on behalf of Algonquin Power & Utilities, Corp. (“Algonquin”), Algonquin (AY Holdco) B.V. (“AY Holdco”), and AAGES (AY Holdings) B.V. (“AY Holdings”) (collectively, the “Reporting Persons”), relates to the ordinary shares, nominal value of $0.10 per share (“Ordinary Shares”), of Atlantica Yield plc (the “Issuer”), a public limited company incorporated under the laws of England and Wales, as described herein in more detail. The Issuer’s principal executive offices are located at Great West House, GW1, 17^th Floor, Great West Road, Brentford, United Kingdom TW8 9DF. Unless otherwise indicated, each capitalized term used but not otherwise defined herein shall have the meaning ascribed to such term in the Original Schedule 13D.

Item 3. Source of Funds

Algonquin, through one of its affiliates, has drawn from the Liberty Power Credit Facility to fund the purchase of the Subscription Shares (as defined herein) and the Atlantica Canada Shares (as defined herein).

Item 4. Purpose of Transaction

Item 4 is hereby amended to include the following:

On May 24, 2019, Algonquin, the Issuer, Atlantica Yield Energy Solutions Canada Inc. (“Atlantica Canada”) and AYES International UK Ltd. entered into an Agreement (the “AYES Shareholder Agreement”) relating to an investment by the Issuer in Atlantica Canada, an entity holding an indirect interest in the Amherst Island wind project, a 75MW wind facility in Canada that was previously wholly-owned by Algonquin. Under the AYES Shareholders Agreement, among other things, Algonquin has the option to exchange, from May 2020, subject to certain circumstances and economic conditions, the occurrence of which Algonquin considers remote, approximately 3.5 million shares of different classes of Atlantica Canada into Ordinary Shares of the Issuer on a one-for-one basis (the “Atlantica Canada Shares”). Such exchange right is subject to the provisions of the Standstill Provision.

On May 22, 2019, the Reporting Persons purchased 1,384,402 Ordinary Shares pursuant to the Subscription Agreement.

The disclosures in Item 6 are herein incorporated by reference.

Item 5. Interest in Securities of the Issuer

Item 5(a), (b) is hereby amended and restated with the following:

(a), (b) The responses of the Reporting Persons to Rows (7) through (13) of the cover pages of this Amendment No. 6 as of the close of business on May 22, 2019, are incorporated herein by reference. After giving effect to the transactions described in Item 4 of this Amendment No. 6, as of the close of business on May 22, 2019, AY Holdings is the direct beneficial owner of 42,942,065 Ordinary Shares, representing approximately 42.3% of the issued and outstanding Ordinary Shares. Algonquin and AY Holdco, through their ownership of AY Holdings, may be deemed to share voting and dispositive power over the Ordinary Shares beneficially owned by AY Holdings.

(c) Except as disclosed in Item 4 of this Amendment No. 6, which is incorporated herein by reference, no Reporting Person has effected any transactions in the Ordinary Shares during the past 60 days, and to the Reporting Persons’ knowledge, none of the directors or executive officers of the Reporting Persons listed on Schedule A to Amendment No. 5 of the Schedule 13D filed on May 13, 2019 effected any transactions in the Ordinary Shares during within the past 60 days.

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Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

Item 6 is hereby amended to include the following:

AYES Shareholder Agreement

On May 24, 2019, Algonquin, the Issuer, Atlantica Yield Energy Solutions Canada Inc. and AYES International UK Limited entered into the AYES Shareholder Agreement relating to an investment by the Issuer in Atlantica Canada, an entity holding an indirect interest in the Amherst Island wind project, a 75MW wind facility in Canada that was previously wholly-owned by Algonquin. Under the AYES Shareholders Agreement, among other things, Algonquin has the option to exchange, from May 2020, subject to certain circumstances and economic conditions, the occurrence of which Algonquin considers remote, the Atlantica Canada Shares into Ordinary Shares of the Issuer at any time on a one-for-one basis. Such exchange right is subject to the provisions of the Standstill Provision.

Item 7. Materials to Be Filed as Exhibits

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SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: May 24, 2019

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Exhibit 99.1

Execution Copy

SHAREHOLDER AGREEMENT

BETWEEN

ATLANTICA YIELD ENERGY SOLUTIONS CANADA INC.

AND

THE SHAREHOLDERS NAMED HEREIN

AND

ATLANTICA YIELD PLC

DATED AS OF

May 24, 2019

TABLE OF CONTENTS

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SHAREHOLDER AGREEMENT

This Agreement (as executed and as it may be amended, modified, supplemented or restated from time to time, as provided herein, this “Agreement”), is dated as of May 24, 2019, between

ATLANTICA YIELD ENERGY SOLUTIONS CANADA INC., a corporation formed under the laws of the Province of British Columbia (the “Company”)

and

AYES INTERNATIONAL UK LIMITED, an United Kingdom corporation (“AYES UK”)

and

ALGONQUIN POWER CO., a trust organized under the laws of the Province of Ontario, (“APCo”) and, together with AYES UK, the “Initial Shareholders”) and each other Person who after the date hereof acquires Shares of the Company and becomes a party to this Agreement by executing a Joinder Agreement (such Persons, collectively with the Initial Shareholders, the “Shareholders”).

and

ATLANTICA YIELD PLC, an United Kingdom limited company (“Atlantica”)

RECITALS

WHEREAS, AYES UK and APCo have formed the Company for the purposes of conducting and operating the Business;

WHEREAS, as of the date hereof, AYES UK owns 100% of the issued and outstanding Class A Common Shares of the Company and APCo owns 100% of the issued and outstanding Class C Common Shares and Class II Common Shares of the Company; and

WHEREAS, the Initial Shareholders and the other parties hereto deem it in their best interests and in the best interests of the Company to set forth in this Agreement their respective rights and obligations in connection with their investment in the Company.

NOW, THEREFORE, in consideration of the mutual covenants and agreements hereinafter set forth and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

ARTICLE 1

DEFINITIONS

Section 1.01    Definitions.

Capitalized terms used herein and not otherwise defined shall have the meanings set forth in this Section 1.01.

“Act” means the Business Corporations Act (British Columbia).

“Affiliate” means with respect to any Person, any other Person who, directly or indirectly (including through one or more intermediaries), controls, is controlled by, or is under common control with, such Person. For purposes of this definition, “control”, when used with respect to any specified Person, shall mean the power to, directly or indirectly, direct or cause the direction of the management and policies of such Person, whether through ownership of voting securities or partnership or other ownership interests, by contract or otherwise; and the terms “controlling” and “controlled” shall have correlative meanings.

“Agreement” has the meaning set forth in the preamble.

“APCo” has the meaning set forth in the preamble.

“APCo Directors” has the meaning set forth in Section 2.01(a)(ii).

“Applicable Law” means all applicable provisions of (a) statutes, laws (including the common law), rules, regulations, decrees, ordinances, codes, proclamations, declarations or orders of any Governmental Authority; (b) any consents or approvals of any Governmental Authority; and (c) any orders, decisions, advisory or interpretative opinions, injunctions, judgments, awards, decrees of, or agreements with, any Governmental Authority.

“Arbitration Notice” has the meaning set forth in Section 9.12(a).

“Arbitrator” has the meaning set forth in Section 9.12(b).

“APCo Directors” has the meaning set forth in Section 3.01.

“AY Shareholders Agreement” has the meaning set forth in Section 3.05.

“AYES UK” has the meaning set forth in the preamble.

“AYES UK Directors” has the meaning set forth in Section 2.01(a)(i).

“Board” has the meaning set forth in Section 2.01(a).

“Business” means the ownership of interests in , either directly or indirectly, renewable power assets, regulated utilities and the provision of ancillary services.

“Business Day” means a day other than a Saturday, Sunday or other day on which banks in the City of Toronto, Ontario, Canada are authorized or required to close.

“Cash Available for Distribution” means all cash received by the Company, less (a) all cash expenses of the Company, including debt services and general and administrative expenses and (b) reasonable reserves established by the Board from time to time to fund reasonably expected obligations.

“Class II Exchange Option” has the meaning set forth in Section 3.01.

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“Class C Exchange Option” has the meaning set forth in Section 3.01

“Company” has the meaning set forth in the preamble.

“Constating Documents” means the articles and the notice of articles of the Company.

“Director” has the meaning set forth in Section 2.01(a).

“Dispute” has the meaning set forth in Section 9.12(a).

“Encumbrance” means any lien, claim, charge, mortgage, pledge, security interest, option, preferential arrangement, right of first refusal, right of first offer, encumbrance, adverse claim or other restriction or limitation of any nature whatsoever.

“Exchange Options” has the meaning set forth in Section 3.01

“Financial Year” means the 12-month period ending on the last day of December.

“Fully Diluted Basis” means, as of any date of determination: (a) with respect to all Shares, all issued and outstanding Shares and all Shares issuable upon the exercise or conversion of any outstanding Share Equivalents as of such date, whether or not such Share Equivalent is at the time exercisable or convertible; or (b) with respect to any specified class or series of Shares, all issued and outstanding Shares of such class or series and all such Shares of such class or series issuable upon the conversion or exercise of any outstanding Share Equivalents as of such date, whether or not such Share Equivalent is at the time exercisable or convertible.

“Government Approval” means any authorization, consent, approval, waiver, exception, variance, order, exemption, publication, filing, declaration, concession, grant, franchise, agreement, permission, permit or licence of, from or with any Governmental Authority, the giving notice to, or registration with, any Governmental Authority or any other action in respect of any Governmental Authority.

“Governmental Authority” means any federal, provincial, territorial, municipal, local or foreign government or political subdivision thereof, or any agency or instrumentality of such government or political subdivision, or any self-regulated organization or other non-governmental regulatory authority or quasi-governmental authority (to the extent that the rules, regulations or orders of such organization or authority have the force of law), or any arbitrator, court or tribunal of competent jurisdiction.

“IFRS” means International Financial Reporting Standards as issued by the International Accounting Standards Board, as adopted by the Canadian Accounting Standards Board.

“Initial Shareholders” has the meaning set forth in the preamble.

“Information” has the meaning set forth in Section 5.01(a).

“Joinder Agreement” means a joinder agreement in form and substance acceptable to the parties, acting reasonably.

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“Notice” has the meaning set forth in Section 9.04.

“Offered Shares” has the meaning set forth in Section 4.02(a).

“Offering Shareholder” has the meaning set forth in Section 4.02(a).

“Offering Shareholder Notice” has the meaning set forth in Section 4.02(b).

“Permitted Transferee” means, with respect to any Shareholder, any Affiliate of such Shareholder.

“Person” means an individual, corporation, body corporate, partnership, joint venture, Governmental Authority, unincorporated organization, trust, association or other entity.

“Purchasing Shareholder” has the meaning set forth in Section 4.02(d).

“Related Party Agreement” means any agreement, arrangement or understanding between the Company and any Shareholder or any Affiliate of a Shareholder or any Director, officer or employee of the Company.

“Representative” means, with respect to any Person, any, and all, directors, officers, employees, consultants, financial advisors, counsel, accountants and other agents of such Person.

“ROFR Notice” has the meaning set forth in Section 4.02(d).

“ROFR Notice Period” has the meaning set forth in Section 4.02(d).

“ROFR Rightholder” has the meaning set forth in Section 4.02(a).

“Securities Act” means the Securities Act (British Columbia), and the rules thereunder, which shall be in effect at the time.

“Share Equivalents” means any stock option and any other security or obligation that is by its terms, directly or indirectly, convertible into or exchangeable or exercisable for Shares, and any option, warrant or other right to subscribe for, purchase or acquire Shares or Share Equivalents (disregarding any restrictions or limitations on the exercise of such rights).

“Shareholders” has the meaning set forth in the preamble.

“Shares” means the shares in the capital of the Company and any securities issued in respect thereof, or in substitution therefor, in connection with any share split, stock dividend or consolidation, or any recapitalization, amalgamation, arrangement, reorganization, exchange or similar reclassification.

“Subsidiary” means with respect to any Person, any other Person of which a majority of the outstanding shares or other equity interests having the power to vote for directors or comparable managers are owned, directly or indirectly, by the first Person.

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“Supermajority Approval” means with respect to any matter that must be approved by the Board (a) the affirmative vote at a meeting of the Board of the entire Board or (b) the unanimous written consent of the entire Board in lieu of a meeting.

“Third Party Purchaser” means any Person who, immediately before the contemplated transaction, (a) does not directly or indirectly own or have the right to acquire any outstanding Shares or (b) is not a Permitted Transferee of any Person who directly or indirectly owns or has the right to acquire any Shares.

“Transfer” means to, directly or indirectly, sell, transfer, assign, pledge, hypothecate or similarly dispose of, either voluntarily or involuntarily, or to enter into any contract, option or other arrangement or understanding with respect to the sale, transfer, assignment, pledge, hypothecation or similar disposition of, any Shares owned by a Person or any interest (including a beneficial interest) in any Shares owned by a Person.

“Voting Shares” means the Class A Common Shares and Class II Common shares in the capital of the Company and any other shares that entitle the holders thereof to vote on the election of directors of the Company.

“Waived ROFR Transfer Period” has the meaning set forth in Section 4.02(f).

Section 1.02    Interpretation.

For purposes of this Agreement: (a) the words “include”, “includes” and “including” shall be deemed to be followed by the words “without limitation”; (b) the word “or” is not exclusive; (c) the words “herein”, “hereof”, “hereby”, “hereto” and “hereunder” refer to this Agreement as a whole; (d) whenever the singular is used herein, the same shall include the plural, and whenever the plural is used herein, the same shall include the singular, where appropriate; and (e) whenever the masculine is used herein, the same shall include the feminine, and whenever the feminine is used herein, the same shall include the masculine, where appropriate. The definitions given for any defined terms in this Agreement shall apply equally to both the singular and plural forms of the terms defined. Whenever the context may require, any pronoun shall include the corresponding masculine, feminine and neuter forms. Unless the context otherwise requires, references herein: (x) to Articles, Sections, Exhibits and Schedules mean the Articles and Sections of, and Exhibits and Schedules attached to, this Agreement; (y) to an agreement, instrument or other document means such agreement, instrument or other document as amended, supplemented and modified from time to time to the extent permitted by the provisions thereof; and (z) to a statute means such statute as amended from time to time and includes any successor legislation thereto and any regulations promulgated thereunder. This Agreement shall be construed without regard to any presumption or rule requiring construction or interpretation against the party drafting an instrument or causing any instrument to be drafted. The Exhibits and Schedules referred to herein shall be construed with, and as an integral part of, this Agreement to the same extent as if they were set forth verbatim herein. Unless otherwise stated in this Agreement, all dollar amounts referred to in this Agreement are stated in Canadian currency.

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Section 1.03    Actions on Non-Business Days.

If any payment is required to be made or other action (including the giving of notice) is required to be taken pursuant to this Agreement on a day which is not a Business Day, then such payment or action shall be considered to have been made or taken in compliance with this Agreement if made or taken on the next succeeding Business Day.

Section 1.04    Calculation of Time.

In this Agreement, a period of days shall be deemed to begin on the first day after the event which began the period and to end at 5:00 p.m. Toronto time on the last day of the period. If any period of time is to expire hereunder on any day that is not a Business Day, the period shall be deemed to expire at 5:00 p.m. Toronto time on the next succeeding Business Day.

Section 1.05    Powers of the Directors and Shareholders.

The Directors shall have all the rights, powers, duties and liabilities arising under the Act or otherwise except to the extent that the provisions of this Agreement restrict the discretion and powers of the Board to manage or to supervise the management of the business and affairs of the Company. The Shareholders shall have all the rights, powers, duties and liabilities of the Directors of the Company, whether arising under the Act or otherwise, with respect to all matters governed by this Agreement to the extent that this Agreement restricts the discretion or powers of the Directors to arrange or supervise the management of the business and affairs of the Company. Any matter requiring the approval of the Directors or holders of a class of Shares shall be evidenced by an instrument or instruments in writing signed by all the Directors or all the Shareholders of that class, as the case may be, or by a resolution duly passed by such Directors or Shareholders at a meeting called and held in accordance with the provisions of the Constating Documents and the provisions of this Agreement.

Section 1.06    Paramountcy.

Subject to the provisions of the Act, in the event of any conflict between the provisions of this Agreement and the Constating Documents, the provisions of this Agreement shall govern. The parties acknowledge that as of the date hereof, conflicts may exist between this Agreement and the Constating Documents. Each of the Shareholders agrees to vote or cause to be voted the Shares owned by it so as to cause the Constating Documents to be amended to resolve each such conflict and any other conflicts in favour of the provisions of this Agreement. In the event of a conflict between this Agreement and any other agreement now or hereafter entered into between the parties, other than amendments to this Agreement contemplated by Section 9.10, the provisions of this Agreement shall prevail.

Section 1.07    Recitals.

The parties hereby mutually covenant and agree that the statements set forth in the foregoing recitals of this Agreement with respect to their Share ownership and relationship to each other form part of this Agreement and each party represents and warrants that its respective statements are true in substance and are correct in all respects

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ARTICLE 2

MANAGEMENT AND OPERATION OF THE COMPANY

Section 2.01    Board of Directors

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Section 2.02    Meetings of the Board of Directors

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Section 2.03    Voting Arrangements.

In addition to any vote or approval of the Board or the Shareholders of the Company required by Applicable Law, without Supermajority Approval the Company shall not, and shall not enter into any commitment to:

Section 2.04    Officers.

The Chief Executive Officer and the Chief Financial Officer of the Company shall be appointed by the Board from time to time. The Board may appoint other officers of the Company from time to time.

Section 2.05    Indemnity by the Company.

To the fullest extent permitted by law, the Company shall indemnify all Directors, officers, former Directors and former officers of the Company, the Shareholders of the Company to the extent that such Shareholders exercise the rights, powers, duties and liabilities of a Director and all Persons who act or acted at the Company’s request as a director or officer (or in a similar capacity) of an entity of which the Company is or was a securityholder or creditor, and his/her/its successors, heirs and legal personal representatives, against all costs, charges and expenses, including any amount paid to settle any action or satisfy a judgment, reasonably incurred by him/her/it in respect of any civil, criminal, administrative, investigative action or proceeding to which he/she is made a party, or in which he/she/it is involved, by reason of being or having been a director or officer of the Company or such other entity or by reason of acting or having acted as a director of the Company or such other entity. The Company shall advance moneys to a Person described above for the costs, charges and expenses of a proceeding referred to above, provided such Person shall repay the moneys if the Person does not fulfil the condition of the following paragraph.

Notwithstanding the preceding paragraph, the Company shall not indemnify a Person identified in the preceding paragraph, unless such Person:

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The intention of this Section is that all Persons referred to in this Section shall have all benefits provided under the indemnification provisions of the Act to the fullest extent permitted by law and the Company shall forthwith pass all resolutions, enter into such agreements and take such other steps as may be required to give full effect to this Section.

Section 2.06    Dividends.

Section 2.07    Books and Records.

The Company shall maintain books and records which shall disclose all financial transactions of the Company in accordance with IFRS, consistently applied. Each Shareholder and its representatives may, at the Shareholder’s cost and expense, examine, audit and obtain copies of the books, records and accounts of the Company.

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Section 2.08    Outside Activities.

ARTICLE 3

EXCHANGE PROVISIONS

Section 3.01    Share Exchange Provisions

APCo or Atlantica shall have the option (the “Class C Exchange Option”), exercisable at any time following the 12 month anniversary of the issuance of the Class C Common Shares, to cause the exchange of all, but not less than all, of the Class C Common Shares of the Company

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for ordinary shares of common stock in the capital of Atlantica (the “Atlantica Shares”) on the basis of one (1) Class C Common Share of the Company for one (1) Atlantica Share. APCo shall have the option (the “Class II Exchange Option” and, together with the “Class C Exchange Option, the “Exchange Options”), exercisable at any time following the 12 month anniversary of the issuance of the Class II Common Shares and provided the Class C Exchange Option has been exercised, to cause the exchange of all, but not less than all, of the Class II Common Shares of the Company for Atlantica Shares on the basis of one (1) Class II Common Share of the Company for one (1) Atlantica Share, it being understood that the potential for such exchange is remote given the structure of the Company’s share capital.

Section 3.02    Exercise of Exchange Provisions.

APCo may exercise the Exchange Options or Atlantica may exercise the Class C Exchange Option by providing a written notice to each of the other parties hereto. Forthwith following the exercise of the Exchange Options, Atlantica shall cause its transfer agent to, issue and deliver to APCo from treasury, in exchange for the certificates evidencing the Class C Common Shares and Class II Common Shares, as the case may be, a certificate, or other evidence of ownership, registered in the name of APCo (or as APCo may otherwise direct) representing the Atlantica Shares issued in exchange for the Class C Common Shares and Class II Common Shares, as the case may be.

Section 3.03    Obligations of Atlantica.

Atlantica covenants and agrees that for so long as the Exchange Options are exercisable, it shall reserve and there shall remain unissued out of its authorized capital a sufficient number of Atlantica Shares to satisfy the obligation herein provided, as such right may be adjusted. Atlantica further covenants and agrees that while the Exchange Options are exercisable, Atlantica shall (a) comply with the securities legislation applicable to it in order that Atlantica not be in default of any requirements of such legislation; (b) use its commercially reasonable best efforts to do or cause to be done all things necessary to preserve and maintain its corporate existence; and (c) at its own expense expeditiously use its commercially reasonable best efforts to obtain the listing of the Atlantica Shares on each stock exchange or over-the-counter market on which its ordinary shares of common stock may be listed from time to time. All Atlantica Shares which shall be issued upon the exercise of the Exchange Options herein provided for, shall be issued as fully paid and non-assessable shares and the holders thereof shall not be liable to Atlantica or its creditors in respect thereof. Note:

Section 3.04    Adjustment.

If, following the issuance of the Class C Common Shares or Class II Common Shares, any action is taken that results in a change to the Atlantica Shares (or other securities or assets into which the Class C Common Shares or Class II Common Shares may be exchanged from to time) the holder of the Class C Common Shares and Class II Common Shares shall be entitled, on the exchange of the Class C Common Shares and Class II Common Shares, to receive the same (or economically equivalent) consideration as they would have received had they been a holder of Atlantica Shares (or other securities or assets into which the Class C Common Shares or Class II Common Shares may be exchange from time to time) at the time such action was taken.

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Section 3.05    Atlantica Shareholders Agreement.

Subject to the following sentence, notwithstanding anything to the contrary herein, to the extent that there is an inconsistency between this Agreement and the provisions of the shareholders agreement dated March 5, 2018, as amended from time to time, between Algonquin Power & Utilities Corp., Abengoa-Algonquin Global Energy Solutions B.V. and Atlantica (the “AY Shareholders Agreement”), the terms of the AY Shareholders Agreement shall govern.

Section 3.06    Limitation on Exchange.

Notwithstanding anything to the contrary herein, in no event shall APCo be required or permitted, directly or indirectly, to subscribe or exchange shares for securities of Atlantica that would cause APCo and/or its Affiliates to hold more than 50% of the total voting rights attached to the Atlantica Shares. To the extent that any exchange contemplated hereby would cause APCo and/or its Affiliates to hold more than 50% of the total voting rights attached to the Atlantica Shares, such transaction shall be deemed to be null and void without any further action by any party.

ARTICLE 4

TRANSFER OF INTERESTS

Section 4.01    General Restrictions on Transfer

“The shares represented by this certificate are subject to the provision of a Shareholders’ Agreement, which Shareholders’ Agreement contains restrictions on the right of the holder to sell, assign, transfer, dispose of, donate or otherwise deal with the shares represented by this certificate. Notice of the terms and conditions of the Shareholders’ Agreement is hereby given.”

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in each case without the consent of any other Shareholder and for any purposes, including as security for any present or future indebtedness of such Shareholder or any Affiliate thereof, provided, however, that any Transfer of any Shares, in any case as a result of foreclosure or other exercise of remedies with respect to any such Encumbrance shall be subject to the other provisions in this Article 4.

Section 4.02    Right of First Refusal

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The Offering Shareholder Notice shall constitute the Offering Shareholder’s offer to Transfer the Offered Shares to the ROFR Rightholders, which offer shall be irrevocable until the end of the ROFR Notice Period.

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ARTICLE 5

CONFIDENTIALITY

Section 5.01    Confidentiality

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ARTICLE 6

INFORMATION RIGHTS

Section 6.01    Financial Statements.

In addition to, and without limiting any rights that a Shareholder may have with respect to inspection of the books and records of the Company under Applicable Law, the Company shall furnish to each Shareholder, the following information:

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Section 6.02    Inspection Rights

ARTICLE 7

REPRESENTATIONS AND WARRANTIES

Section 7.01    Representations and Warranties.

Each Shareholder, severally and not jointly, represents and warrants to the Company and each other Shareholder that:

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Section 7.02    Specified Financial Institution.

Atlantica represents and warrants that it, and any entity related to it, is not a “Specified Financial Institution” as such term is defined in the Income Tax Act (Canada). Atlantica further covenants that for so long as APCo is a holder of Class C shares neither Atlantica, nor any entity related to it, will become a “Specified Financial Institution” as such term is defined in the Income Tax Act (Canada).

ARTICLE 8

TERM AND TERMINATION

Section 8.01    Termination.

This Agreement shall terminate upon the earliest of:

Section 8.02    Effect of Termination

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ARTICLE 9

MISCELLANEOUS

Section 9.01    Atlantica Shareholder Approval.

In the event that Atlantica cannot fulfill any obligation in this Agreement that is subject to the approval of its shareholders, it shall not be considered a breach of this Agreement if Atlantica did not fulfill such obligation due to Atlantica not being able to obtain the aforementioned approval or for any legal reason, provided it used its best efforts to obtain the required approvals.

Section 9.02    Expenses.

Except as otherwise expressly provided in this Agreement, all costs and expenses, including fees and disbursements of counsel, financial advisors and accountants, incurred in connection with this Agreement and the transactions contemplated hereby shall be paid by the party incurring such costs and expenses.

Section 9.03    Release of Liability.

If any Shareholder shall Transfer all of the Shares held by such Shareholder in compliance with the provisions of this Agreement without retaining any interest therein, then such Shareholder shall cease to be a party to this Agreement and shall be relieved and have no further liability arising hereunder for events occurring from and after the date of such Transfer.

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Section 9.04    Notices.

All notices, requests, consents, claims, demands, waivers and other communications hereunder (each, a “Notice”) shall be in writing and shall be deemed to have been given: (a) when delivered by hand (with written confirmation of receipt); (b) when received by the addressee if sent by a nationally recognized overnight courier (receipt requested); (c) on the date sent by facsimile or e-mail of a PDF document (with confirmation of transmission) if sent during normal business hours of the recipient, and on the next Business Day if sent after normal business hours of the recipient; or (d) on the third day after the date mailed, by certified or registered mail, return receipt requested, postage prepaid. Such Notice must be sent to the respective parties at the following addresses (or at such other address for a party as shall be specified in a Notice given in accordance with this Section 9.04):

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Section 9.05    Headings.

The headings in this Agreement are for reference only and shall not affect the interpretation of this Agreement.

Section 9.06    Severability.

If any term or provision of this Agreement is invalid, illegal or unenforceable in any jurisdiction, such invalidity, illegality or unenforceability shall not affect any other term or provision of this Agreement or invalidate or render unenforceable such term or provision in any other jurisdiction.

Section 9.07    Entire Agreement.

This Agreement and the Constating Documents constitute the sole and entire agreement of the parties with respect to the subject matter contained herein and therein, and supersede all prior and contemporaneous understandings and agreements, both written and oral, with respect to such subject matter. In the event of any inconsistency or conflict between this Agreement and any Constating Document, the Shareholders and the Company shall, to the extent permitted by Applicable Law, amend such Constating Document to comply with the terms of this Agreement.

Section 9.08    Successors and Assigns.

This Agreement shall be binding upon and shall enure to the benefit of the parties hereto and their respective successors and permitted assigns.

Section 9.09    No Third-Party Beneficiaries.

This Agreement is for the sole benefit of the parties hereto and their permitted assigns and nothing herein, express or implied, is intended to or shall confer upon any other Person or entity any legal or equitable right, benefit or remedy of any nature whatsoever under or by reason of this Agreement.

Section 9.10    Amendment and Modification; Waiver.

This Agreement may only be amended, modified or supplemented by an agreement in writing signed by each party hereto. No waiver by any party of any of the provisions hereof shall be effective unless explicitly set forth in writing and signed by the party so waiving. No waiver by any party shall operate or be construed as a waiver in respect of any failure, breach or default not expressly identified by such written waiver, whether of a similar or different character, and whether occurring before or after that waiver. No failure to exercise, or delay in exercising, any right, remedy, power or privilege arising from this Agreement shall operate or be construed as a

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waiver thereof; nor shall any single or partial exercise of any right, remedy, power or privilege hereunder preclude any other or further exercise thereof or the exercise of any other right, remedy, power or privilege.

Section 9.11    Governing Law.

All issues and questions concerning the application, construction, validity, interpretation and enforcement of this Agreement shall be governed by and construed in accordance with the laws of the province of British Columbia and the federal laws of Canada applicable therein.

Section 9.12    Dispute Resolution

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Section 9.13    Equitable Remedies.

Each party hereto acknowledges that the other parties hereto would be irreparably damaged in the event of a breach or threatened breach by such party of any of its obligations under this Agreement and hereby agrees that, in the event of a breach or a threatened breach by such party of any such obligations, each of the other parties hereto shall, in addition to any and all other rights and remedies that may be available to them in respect of such breach, be entitled to seek an injunction from a court of competent jurisdiction (without any requirement to post a bond or other security) granting such parties specific performance by such party of its obligations under this Agreement. If any party commences an action to enforce the covenants contained in this Agreement (or obtain any other remedy in respect of any breach thereof), the prevailing party in the action shall be entitled to receive, in addition to all other damages to which it may be entitled, the costs incurred by such party in conducting the action, including reasonable legal fees, disbursements and charges.

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Section 9.14    Language.

The parties have required that this Agreement and all documents and notices resulting from it be drawn up in English. Les parties aux présents ont exigés que la présente convention ainsi que tous les documents et avis qui s’y rattachent ou qui en découleront soit rédigés en la langue anglaise.

Section 9.15    Counterparts.

This Agreement may be executed in counterparts, each of which shall be deemed an original, but all of which together shall be deemed to be one and the same agreement. A signed copy of this Agreement delivered by facsimile, e-mail or other means of electronic transmission shall be deemed to have the same legal effect as delivery of an original signed copy of this Agreement.

[SIGNATURE PAGE FOLLOWS]

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed as of the date first written above by their respective officers thereunto duly authorized.

[Signature page – AYES Canada Shareholders Agreement]

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