Item 1. Security and Issuer
This Amendment No. 9 (this “Amendment No. 9”) 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, 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, 17th 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. 9 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.
Item 4. Purpose of Transaction
Item 4 is
hereby amended as follows:
On December 9, 2020, Algonquin entered into a Subscription Agreement Relating to Ordinary Shares in the Issuer
(the “Subscription Agreement”) with the Issuer, pursuant to which Algonquin, through AY Holdings, and subject to the terms and conditions set forth in the Subscription Agreement, subscribed for the lower of (a) the sum of (i)
3,496,400 Ordinary Shares and (ii) if the over-allotment option (pursuant to an Underwriting Agreement between the Issuer and BofA Securities, Inc., dated on or about the date of the Subscription Agreement) is exercised in whole or in part,
such number of additional Ordinary Shares as will result in the proportion of Ordinary Shares held by AY Holdings immediately following the closing of the transaction contemplated by the Subscription Agreement being equal to the proportion of
Ordinary Shares held by AY Holdings on the date of the Subscription Agreement; and (b) the highest number of Ordinary Shares which would result in the proportion of Ordinary Shares held by AY Holdings immediately following the closing of the
transaction contemplated by the Subscription Agreement being no greater than the proportion of Ordinary Shares held by AY Holdings on the date of the Subscription Agreement, at a per share price of $33.00. Pursuant to the Subscription Agreement, the
Issuer will pay to Algonquin a commitment fee of 1.25% of the purchase price. The transaction is expected to close on January 7, 2021 (or such other date as may be agreed by Algonquin and the Issuer), subject to certain closing conditions, more
fully set forth in the Subscription Agreement.
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. 9, as of the close
of business on December 9, 2020, are incorporated herein by reference. As of the close of business on December 9, 2020, AY Holdings is the direct beneficial owner of 44,942,065 Ordinary Shares, representing approximately 44.2% 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) Since the filing of Amendment No. 8 to the Schedule 13D, no Reporting Person has effected any transactions in the Ordinary Shares, and
to the Reporting Persons’ knowledge, none of the directors or executive officers of the Reporting Persons listed on Schedule A effected any transactions in the Ordinary Shares.
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