ABC AmerisourceBergen Corp

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934

(Amendment No. 12)*

AMERISOURCEBERGEN CORPORATION

(Name of Issuer)

Common Stock, par value $0.01 per share

(Title of Class of Securities)

03073E105

(CUSIP Number)

Danielle Gray

Executive Vice President, Global Chief Legal Officer

Walgreens Boots Alliance, Inc.

108 Wilmot Road

Deerfield, Illinois 60015

(847) 315-2500

With a copy to:

Lillian Tsu

Cleary Gottlieb Steen & Hamilton LLP

One Liberty Plaza

New York, NY 10006

(212) 225-2000

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

May 11, 2023

(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 §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“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).

CUSIP No. 03073E105

13D

CUSIP No. 03073E105

CUSIP No. 03073E105

This Amendment No. 12 to Schedule 13D (this “Amendment No. 12”) amends and supplements the Schedule 13D (the “Schedule 13D”) relating to the common stock, $0.01 par value per share (“Common Stock”), of AmerisourceBergen Corporation, a Delaware corporation (the “Issuer”), originally filed with the Securities and Exchange Commission (the “SEC”) on April 15, 2014, as amended by Amendment No. 1 thereto filed on January 16, 2015, Amendment No. 2 thereto filed on January 25, 2016, Amendment No. 3 thereto filed on March 22, 2016, Amendment No. 4 thereto filed on August 25, 2016, Amendment No. 5 thereto filed on November 14, 2016, Amendment No. 6 thereto filed on January 6, 2021, Amendment No. 7 thereto filed on June 3, 2021, Amendment No. 8 thereto filed on May 12, 2022, Amendment No. 9 thereto filed on August 4, 2022, Amendment No. 10 thereto filed on November 9, 2022 and Amendment No. 11 thereto filed on December 12, 2022. Terms used but not defined in this Amendment No. 12 have the respective meanings given to such terms in the original Schedule 13D, as previously amended.

Item 2 is amended and supplemented as follows:

This Amendment No. 12 is being filed by: (i) Walgreens Boots Alliance Holdings LLC, a Delaware limited liability company (“WBA Holdings”) (f/k/a WAB Holdings LLC); (ii) WBA Investments, Inc., a Delaware corporation (“WBA Investments”); and (iii) Walgreens Boots Alliance, Inc., a Delaware corporation (“WBA”). WBA Holdings, WBA Investments and WBA are collectively referred to as the “Reporting Persons.”

WBA Holdings was formed solely for the purpose of investing in the Issuer. All of the shares of Common Stock reported as beneficially owned by any Reporting Person in this Schedule 13D are held by WBA Holdings. WBA Holdings is a wholly owned subsidiary of WBA Investments. WBA Investments is a wholly owned subsidiary of WBA. WBA, together with its subsidiaries, including the Reporting Persons, is a global pharmacy-led, health and wellbeing enterprise.

The principal business office of each of the Reporting Persons is: c/o Walgreens Boots Alliance, Inc., 108 Wilmot Road, Deerfield, Illinois 60015.

Attached as Annex A hereto and incorporated herein by reference is a list containing the (a) name, (b) residence or business address, (c) present principal occupation or employment and the name, principal business address of any corporation or other organization in which such employment is conducted, and (d) citizenship, in each case, of each director and executive officer of the Reporting Persons, as applicable.

During the last five years, each Reporting Person and, to the knowledge of such Reporting Person, each person listed in Annex A with respect to such Reporting Person, has not been convicted in any criminal proceeding (excluding traffic violations or similar misdemeanors) and has not been a party to a civil proceeding of any judicial or administrative body of competent jurisdiction as a result of which such person 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 of any violation with respect to such laws.

Item 4 is amended and supplemented as follows by adding the following:

May 2023 Transactions and Concurrent Share Repurchase

On May 11, 2023, WBA Holdings entered into variable pre-paid forward sale contracts (the “Contracts”) with each of Wells Fargo Bank, National Association, JPMorgan Chase Bank, National Association, New York Branch, Bank of America, N.A., and Mizuho Markets Americas LLC (the “financial institutions”), executed in reliance on Rule 144 of the Securities Act of 1933, as amended (the “May 2023 Transactions”). The Contracts obligate WBA Holdings to deliver to the financial institutions in the aggregate up to 4,590,000 shares of Common Stock (or, at WBA Holdings’ election, an equivalent amount of cash based on the volume-weighted average price of the Common Stock) and may entitle WBA Holdings to an additional cash payment in respect of each valuation date of the Contracts. In exchange for

assuming these obligations, WBA Holdings received cash payments from the financial institutions in an aggregate amount of approximately $644 million on or about the date of entering into the Contracts. WBA Holdings also pledged 4,590,000 shares of Common Stock (the “Pledged Shares”) in the aggregate to the financial institutions or their affiliates to secure its obligations under the Contracts, and retained certain dividend and voting rights on the Pledged Shares. Under the May 2023 Transactions, WBA will continue to participate in upside and downside between the Floor Price and the Cap Price (as those terms are defined herein) with respect to the Pledged Shares underlying the Contracts.

In respect of each of the 30 valuation dates under the Contracts, scheduled from June 2, 2025 to July 16, 2025, inclusive, the aggregate number of shares of Common Stock to be delivered to the financial institutions or cash to be delivered to (or by) the financial institutions is to be determined as follows: WBA Holdings may, at its election, subject to certain conditions: (1) be obligated to deliver to the financial institutions the full number of shares to which such valuation date relates and will receive an additional cash payment determined as follows: (a) if the volume-weighted average price of the Common Stock on such valuation date (the “Reference Price”) is less than or equal to $151.9853 (the “Floor Price”), the additional cash payment would be zero, (b) if the Reference Price is greater than the Floor Price but less than or equal to $196.3855 (the “Cap Price”), the additional cash payment would equal the number of shares of Common Stock to which such valuation date relates multiplied by the excess of the Reference Price over the Floor Price and (c) if the Reference Price is greater than the Cap Price, the additional cash payment would equal the number of shares of Common Stock to which such valuation date relates multiplied by the excess of the Cap Price over the Floor Price. Alternatively, (2) WBA Holdings may elect, subject to certain conditions, to not receive any additional cash payment and be obligated to deliver to the financial institutions in the aggregate a number of shares of Common Stock (or the cash value thereof at the Reference Price) determined as follows: (a) if the Reference Price is less than or equal to the Floor Price, the full number of shares to which such valuation date relates, (b) if the Reference Price is greater than the Floor Price but less than or equal to the Cap Price, a number of shares of Common Stock having a value (based on the Reference Price) equal to the number of shares of Common Stock to which such valuation date relates multiplied by the Floor Price and (c) if the Reference Price is greater than the Cap Price, a number of shares of Common Stock having a value (based on the Reference Price) equal to the number of shares of Common Stock to which such valuation date relates multiplied by the sum of the Floor Price and the excess of the Reference Price over the Cap Price.

In addition, the Issuer and WBA Holdings concurrently entered into a share repurchase agreement (the “Share Repurchase Agreement”) whereby the Issuer repurchased directly from WBA Holdings 292,792 shares of the Common Stock at the per share block price of the May 2023 Transactions used as the reference price to determine the terms of the Contracts (the “Concurrent Share Repurchase”).

The May 2023 Transactions and Concurrent Share Repurchase are part of WBA’s efforts to continue to optimize its capital allocation to reduce indebtedness and for general corporate purposes.

From time to time, WBA undertakes a review of its strategic and capital allocation priorities. As part of this review, WBA may effect one or more further sales of Common Stock. Any such sales, which may be undertaken at any time without further notice, may take a number of forms, including registered public offerings effected pursuant to WBA’s registration rights under the A&R Shareholders Agreement (which offerings may be underwritten and/or marketed), unregistered or registered block trades, unregistered market or private sales, pledges, hedges, forward sales and other derivative transactions.

Decisions to effect any such sales, as well as the size and timing thereof, are also subject to a number of factors outside of the control of WBA, including current and anticipated future trading prices of the shares of Common Stock or other securities of the Issuer, the financial condition, results of operations and prospects of the Issuer and general economic, financial market and industry conditions, other investment and/or business opportunities available to the Reporting Persons, strategic considerations in respect of the Reporting Persons, general stock market and economic conditions, tax considerations and other factors. WBA will periodically consider such sales opportunistically based on such factors and, as a result, the ultimate number of shares of Common Stock that may be sold by WBA, if any, is not ascertainable.

All existing commercial agreements between WBA and the Issuer (including the US pharmaceutical distribution agreement), as well as the A&R Shareholders Agreement, remain in full force and effect in accordance with their respective terms.

Ornella Barra remains a director of the Issuer. It is currently expected that Ms. Barra (or another designee of WBA) will remain a director of the Issuer unless and until the occurrence of a Walgreens Investor Rights Termination Event (as defined in the A&R Shareholders Agreement).

The foregoing summary of the Contracts and the Concurrent Share Repurchase does not purport to be complete and is qualified in its entirety by reference to the full text of the Form of Master Confirmation and the Share Repurchase Agreement, copies of which are attached hereto as Exhibit 99.19 and Exhibit 99.20, respectively, and are incorporated herein by reference.

Item 5 is amended and supplemented as follows:

(a) and (b). The ownership percentages set forth below are based on 202,173,212 shares of Common Stock outstanding after giving effect to the Concurrent Share Repurchase (as represented by the Issuer in its Current Report on Form 8-K filed on 15, 2023). WBA Holdings may be deemed to beneficially own 33,366,388 shares of Common Stock, representing approximately 16.50% of the total number of shares of Common Stock outstanding, as of the filing of this Amendment No. 12.

By virtue of relationships reported in Item 2, each of WBA Investments and WBA may be deemed to share the power to vote or direct to vote or to direct the voting of, and to dispose of or to direct the disposition of and, accordingly, may be deemed to beneficially own the 33,366,388 shares of Common Stock held by WBA Holdings, representing approximately 16.50% of the total number of shares of Common Stock outstanding, as of the filing of this Amendment No. 12.

Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission by any Reporting Person (other than WBA Holdings) that it is the beneficial owner of any shares of Common Stock for purposes of Section 13(d) of the Exchange Act, or for any other purpose, and such beneficial ownership is expressly disclaimed.

(c) With respect to each Reporting Person, such Reporting Person and, to the knowledge of such Reporting Person, the persons listed in Annex A hereto with respect to such Reporting Person, have not effected any transaction in shares of Common Stock in the past 60 days.

(d) Other than WBA and its subsidiaries, including WBA Holdings and WBA Investments and the persons listed in Annex A hereto with respect thereto, no other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of the shares of Common Stock covered by this Schedule 13D; except that, pursuant to the terms of the Contracts, the financial institutions have certain rights to receive payments in respect of extraordinary cash dividends that may be paid by the Issuer with respect to the shares of Common Stock pledged under such Contracts.

(e) Not applicable.

The information set forth under Item 4 is hereby incorporated by reference.

SIGNATURES

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

Dated: May 15, 2023

ANNEX A

WALGREENS BOOTS ALLIANCE HOLDINGS LLC

OFFICERS

Unless otherwise noted, the business address for each person listed below is c/o Walgreens Boots Alliance, Inc., 108 Wilmot Road, Deerfield, Illinois 60015. To the knowledge of WBA, all officers listed below are United States citizens.

Manmohan Mahajan, President

Present Principal Occupation: Senior Vice President, Global Controller and Chief Accounting Officer, Walgreens Boots Alliance, Inc.

Joseph B. Amsbary, Jr., Vice President and Secretary

Present Principal Occupation: Senior Vice President and Corporate Secretary, Walgreens Boots Alliance Inc.

Mark Weisz, Vice President

Present Principal Occupation: Senior Vice President, Global Tax, Walgreens Boots Alliance, Inc.

Omorlie Harris, Treasurer

Present Principal Occupation: Senior Vice President, Global Treasurer, Walgreens Boots Alliance, Inc.

Michael Emerson, Vice President, Tax

Present Principal Occupation: Vice President of Tax Audits and Controversy, Walgreen Co.

Brittany Mack, Assistant Treasurer

Present Principal Occupation: Senior Director, Tax Operations and Compliance, Walgreen Co.

WBA INVESTMENTS, INC.

DIRECTORS

Unless otherwise noted, the business address for each person listed below is c/o Walgreens Boots Alliance, Inc., 108 Wilmot Road, Deerfield, Illinois 60015. To the knowledge of WBA, each director listed below is a United States citizen.

Manmohan Mahajan, President

Present Principal Occupation: Senior Vice President, Global Controller and Chief Accounting Officer, Walgreens Boots Alliance, Inc.

Joseph B. Amsbary, Jr., Senior Vice President and Secretary

Present Principal Occupation: Senior Vice President and Corporate Secretary, Walgreens Boots Alliance, Inc.

Mark Weisz, Vice President

Present Principal Occupation: Senior Vice President, Global Tax, Walgreens Boots Alliance, Inc.

OFFICERS

Unless otherwise noted, the business address for each person listed below is c/o Walgreens Boots Alliance, Inc., 108 Wilmot Road, Deerfield, Illinois 60015. To the knowledge of WBA, all officers listed below are United States citizens..

Manmohan Mahajan, President

Present Principal Occupation: Senior Vice President, Global Controller and Chief Accounting Officer, Walgreens Boots Alliance, Inc.

Mark Weisz, Vice President

Present Principal Occupation: Senior Vice President, Global Tax, Walgreens Boots Alliance, Inc.

Joseph B. Amsbary, Jr., Senior Vice President and Secretary

Present Principal Occupation: Senior Vice President and Corporate Secretary, Walgreens Boots Alliance, Inc.

Omorlie Harris, Treasurer

Present Principal Occupation: Senior Vice President, Global Treasurer, Walgreens Boots Alliance, Inc.

Michael Emerson, Vice President, Tax

Present Principal Occupation: Vice President of Tax Audits and Controversy, Walgreen Co.

Brittany Mack, Assistant Treasurer

Present Principal Occupation: Senior Director, Tax Operations and Compliance, Walgreen Co.

WALGREENS BOOTS ALLIANCE, INC.

DIRECTORS

Unless otherwise noted, the business address for each person listed below is c/o Walgreens Boots Alliance, Inc., 108 Wilmot Road, Deerfield, Illinois 60015. To the knowledge of WBA, all directors listed below are United States citizens, except for Janice M. Babiak, who is a citizen of the United States and the United Kingdom; John A. Lederer, who is a citizen of Canada; Stefano Pessina, who is a citizen of Monaco; and Dominic P. Murphy, who is a citizen of the Republic of Ireland.

Janice M. Babiak

Present Principal Occupation: Former Partner, Ernst & Young LLP

Inderpal S. Bhandari

Present Principal Occupation: Global Chief Data Officer, IBM Corporation

Rosalind Gates Brewer

Present Principal Occupation: Chief Executive Officer, Walgreens Boots Alliance, Inc.

Ginger L. Graham

Present Principal Occupation: Lead Independent Director, Walgreens Boots Alliance, Inc. and Former President and Chief Executive Officer, Amylin Pharmaceuticals

Bryan C. Hanson

Present Principal Occupation: President, CEO and Chairman, Zimmer Biomet

Valerie B. Jarrett

Present Principal Occupation: Chief Executive Officer of the Obama Foundation and Former Senior Advisor to President Barack Obama

John A. Lederer

Present Principal Occupation: Interim Chief Executive Officer, Staples, Inc. and Senior Advisor, Sycamore Partners

Dominic P. Murphy

Business Address: 111 Strand, London WC2R 0AG, United Kingdom

Present Principal Occupation: Managing Partner and Co-Head of UK Investments, CVC Capital Partners

Stefano Pessina

Business address: 24 Boulevard du Ténao, 98000 Monaco

Present Principal Occupation: Executive Chairman, Walgreens Boots Alliance, Inc.

Nancy M. Schlichting

Present Principal Occupation: Former Chief Executive Officer, Henry Ford Health System

OFFICERS

Unless otherwise noted, the business address for each person listed below is c/o Walgreens Boots Alliance, Inc., 108 Wilmot Road, Deerfield, Illinois 60015. To the knowledge of WBA, all executive officers listed below are United States citizens, except for Stefano Pessina and Ornella Barra, who are each citizens of Monaco; and James Kehoe, who is a citizen of the Republic of Ireland.

Stefano Pessina

Business Address: 24 Boulevard du Ténao, 98000 Monaco

Present Principal Occupation: Executive Chairman of the Board, Walgreens Boots Alliance, Inc.

Ornella Barra

Business Address: 24 Boulevard du Ténao, 98000 Monaco

Present Principal Occupation: Chief Operating Officer, International, Walgreens Boots Alliance, Inc.

Rosalind Gates Brewer

Present Principal Occupation: Chief Executive Officer, Walgreens Boots Alliance, Inc.

James Kehoe

Present Principal Occupation: Executive Vice President and Global Chief Financial Officer, Walgreens Boots Alliance, Inc.

Danielle Gray

Present Principal Occupation: Executive Vice President and Global Chief Legal Officer, Walgreens Boots Alliance, Inc.

Holly May

Present Principal Occupation: Executive Vice President and Global Chief Human Resources Officer, Walgreens Boots Alliance, Inc.

Kevin Ban, M.D.

Present Principal Occupation: Executive Vice President and Global Chief Medical Officer, Walgreens Boots Alliance, Inc.

Tracey Brown

Present Principal Occupation: President, Walgreens Retail, and Chief Customer Officer

Rick Gates

Present Principal Occupation: Senior Vice President and Chief Pharmacy Officer, Walgreens Boots Alliance, Inc.

John Driscoll

Present Principal Occupation: Executive Vice President, President of U.S. Healthcare