Atlantica Sustainable Infrastructure (AY) SC 13D/AAtlantica Sustainable Infrastructure / ALGONQUIN POWER & UTILITIES ownership change

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D/A

(Amendment No. 11)

Under the Securities Exchange Act of 1934

Atlantica Sustainable Infrastructure 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

Matthew Gilroy

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)

August 4, 2021

(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. 11 (this “Amendment No. 11”) to the Schedule 13D initially 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, as amended by Amendment No. 4 filed on February 15, 2019, as amended by Amendment No. 5 filed on May 13, 2019 (“Amendment No. 5”), as amended by Amendment No. 6 filed on May 24, 2019, as amended by Amendment No. 7 filed on June 3, 2019 (“Amendment No. 7”), as amended by Amendment No. 8 filed on April 6, 2020, as amended by Amendment No. 9 filed on December 10, 2020 (“Amendment No. 9”), as amended by Amendment No. 10 filed on January 7, 2021, 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 Sustainable Infrastructure 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 2. Identity and Background

Item 2 is hereby amended as follows:

Schedule A to the Original Schedule 13D is hereby amended and restated as set forth on Schedule A to this Amendment No. 11 and incorporated by reference herein are the names, business addresses, present principal occupations or employments, and citizenship of each director and executive officer of the Reporting Persons.

(d), (e)    During the last five years, none of the Reporting Persons and none of the persons set forth on Schedule A (i) has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violations with respect to such laws.

Item 3. Source and Amount of Funds or Other Consideration

Item 3 is hereby amended as follows:

On March 13, 2020, Arthur Kacprzak, Algonquin’s Chief Financial Officer, in his individual capacity, used approximately $2,231.00 from his personal funds to purchase 100 Ordinary Shares on the open market at $22.31 per share.

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Item 4. Purpose of Transaction

Item 4 is hereby amended as follows:

The Issuer has established an “at-the-market program” for an aggregate offering size of up to $150,000,000 (the “ATM Program”), by which the Issuer may offer and sell its Ordinary Shares at any time and from time to time through J.P. Morgan Securities LLC (the “Agent”), through ordinary brokers’ transactions through the NASDAQ Global Select Market at market prices, in block transactions or as otherwise agreed between the Issuer and the Agent.

In connection with the ATM Program and for purposes of maintaining Algonquin’s existing preemptive right under the Shareholders Agreement, dated as of March 5, 2018, by and among Algonquin, Abengoa-Algonquin Global Energy Solutions B.V. and the Issuer, on August 3, 2021, Algonquin entered into a letter agreement (the “ATM Plan Letter Agreement”) with the Issuer, pursuant to which the Issuer will, for each quarter during which the Issuer sells Ordinary Shares under the ATM Program, offer Algonquin or one or more of its subsidiaries as designated by Algonquin (the “Algonquin Investor”) the right but not the obligation to purchase up to a number of Ordinary Shares to maintain its percentage interest in the Issuer at the average price of the Ordinary Shares sold in the previous quarter under the ATM Program (the “ATM Preemptive Right”). If the Algonquin Investor exercises the ATM Preemptive Right, subject to certain conditions described in the ATM Plan Letter Agreement, the Issuer and the Algonquin Investor will enter into a subscription agreement with a settlement date up to the later of (a) one hundred and eighty calendars days following Algonquin’s notice that it is subscribing for the Ordinary Shares (the “Investor Notice”), provided that such date is prior to January 1, 2023, and (b) the twelfth business day following the Investor Notice.

Mr. Kacprzak holds his Ordinary Shares for investment purposes. Mr. Kacprzak may, from time to time, depending on market conditions and other considerations, purchase additional shares or dispose of some or all of the Ordinary Shares held by him.

Item 5. Interest in Securities of the Issuer

Item 5 is hereby amended to include the following:

(a), (b) The responses of the Reporting Persons to Rows (7) through (13) of the cover pages of this Amendment No. 11, as of the close of business on August 4, 2021, are incorporated herein by reference. As of the close of business on August 4, 2021, AY Holdings is the direct beneficial owner of 48,962,925 Ordinary Shares, representing approximately 44.2% of the issued and outstanding Ordinary Shares (based upon 110,833,204 Ordinary Shares issued and outstanding, as provided by the Issuer). 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. Separately, Mr. Kacprzak, Algonquin’s Chief Financial Officer, in his individual capacity, beneficially owns (and has sole voting and dispositive power over) 100 Ordinary Shares.

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(c) No Reporting Person and to the Reporting Persons’ knowledge, none of the directors or executive officers of the Reporting Persons listed on Schedule A, has effected any transactions in the Ordinary Shares during the past 60 days.

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

Item 6 is hereby amended to include the following:

The disclosure in Item 4 of this Amendment No. 11 is incorporated by reference.

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: August 4, 2021

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Schedule A

Directors and Executive Officers of the Reporting Persons

The following tables set forth the name, business address, present principal occupation or employment and citizenship of each director and executive officer of the Reporting Persons:

ALGONQUIN POWER & UTILITIES CORP. DIRECTORS

ALGONQUIN POWER & UTILITIES CORP. EXECUTIVE OFFICERS

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ALGONQUIN (AY HOLDCO) B.V. DIRECTORS

AAGES (AY HOLDINGS) B.V. DIRECTORS

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