Item 9A. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

The Company maintains disclosure controls and procedures that are intended to ensure that information required to be disclosed in the Company's reports submitted under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), is recorded, processed, summarized, and reported within the time periods specified in the rules and forms of the SEC. These controls and procedures also are intended to ensure that information required to be disclosed in such reports is accumulated and communicated to management to allow timely decisions regarding required disclosures.

The Company's Chief Executive Officer and Chief Financial Officer, with the participation of other members of the Company's management, have evaluated the effectiveness of the Company's disclosure controls and procedures (as such term is defined in Rules 13a — 15(e) and 15d — 15(e) under the Exchange Act) and have concluded that the Company's disclosure controls and procedures were effective for their intended purposes as of the end of the period covered by this report.

Changes in Internal Control over Financial Reporting

There were no changes during the fiscal quarter ended September 30, 2021 in the Company's internal control over financial reporting that materially affected, or are reasonably likely to materially affect, those controls.

MANAGEMENT'S REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING

The management of AmerisourceBergen Corporation ("AmerisourceBergen" or the "Company") is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934, as amended. AmerisourceBergen's internal control over financial reporting is designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. The Company's internal control over financial reporting includes those policies and procedures that:

(i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the Company;

(ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with U.S. generally accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance with authorizations of management and directors of the Company; and

(iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the Company's assets that could have a material effect on the financial statements.

Because of inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

AmerisourceBergen's management assessed the effectiveness of AmerisourceBergen's internal control over financial reporting as of September 30, 2021. In making this assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control — Integrated Framework (2013). Based on management's assessment and those criteria, management has concluded that AmerisourceBergen's internal control over financial reporting was effective as of September 30, 2021.

During the third quarter of fiscal 2021, the Company acquired Alliance Healthcare. As permitted by related SEC staff interpretive guidance for newly acquired businesses, Alliance Healthcare has been excluded from management's assessment of the effectiveness of the Company's internal control over financial reporting as of September 30, 2021. In the aggregate, Alliance Healthcare represented 22% of the total assets (of which 10% represented acquired goodwill and intangibles) and 3% of total revenue of the Company as of and for the fiscal year ended September 30, 2021.

AmerisourceBergen's independent registered public accounting firm, Ernst & Young LLP, has issued an attestation report on the effectiveness of AmerisourceBergen's internal control over financial reporting. This report is set forth below.

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and the Board of Directors of AmerisourceBergen Corporation

Opinion on Internal Control over Financial Reporting

We have audited AmerisourceBergen Corporation and subsidiaries' internal control over financial reporting as of September 30, 2021, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, AmerisourceBergen Corporation and subsidiaries (the Company) maintained, in all material respects, effective internal control over financial reporting as of September 30, 2021, based on the COSO criteria.

As indicated in the accompanying Management’s Report on Internal Control Over Financial Reporting, management’s assessment of and conclusion on the effectiveness of internal control over financial reporting did not include the internal controls of Alliance Healthcare, which is included in the 2021 consolidated financial statements of the Company and constituted 22% of total assets as of September 30, 2021 and 3% of revenues for the year then ended. Our audit of internal control over financial reporting of the Company also did not include an evaluation of the internal control over financial reporting of Alliance Healthcare.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the 2021 consolidated financial statements of the Company and our report dated November 23, 2021 expressed an unqualified opinion thereon.

Basis for Opinion

The Company's management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company's internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company's internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Philadelphia, Pennsylvania

November 23, 2021

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