CHARLES RIVER LABORATORIES INTERNATIONAL INC

To the Board of Directors and Shareholders of Charles River Laboratories International, Inc.:

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of Charles River Laboratories International, Inc. and its subsidiaries (the “Company”) as of December 30, 2023 and December 31, 2022, and the related consolidated statements of income, comprehensive income, changes in equity and cash flows for each of the three years in the period ended December 30, 2023, including the related notes (collectively referred to as the “consolidated financial statements”). We also have audited the Company's internal control over financial reporting as of December 30, 2023, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 30, 2023 and December 31, 2022, and the results of its operations and its cash flows for each of the three years in the period ended December 30, 2023 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 30, 2023, based on criteria established in Internal Control - Integrated Framework (2013) issued by the COSO.

Basis for Opinions

The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Report on Internal Control Over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on the Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (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 audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.

Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

As described in Management’s Report on Internal Control Over Financial Reporting, management has excluded Noveprim Group (“Noveprim”) from its assessment of internal control over financial reporting as of December 30, 2023, because it was acquired by the Company in a purchase business combination during 2023. We have also excluded Noveprim from our audit of internal control over financial reporting. Noveprim is a subsidiary whose total assets and total revenues excluded from management’s assessment and our audit of internal control over financial reporting represent less than 1%, respectively, of the related consolidated financial statement amounts as of and for the year ended December 30, 2023.

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 (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 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 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.

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current period audit of the consolidated financial statements that were communicated or required to be communicated to the audit committee and that (i) relate to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Acquisition of Noveprim – Valuation of Biological Assets

As described in Notes 1 and 2 to the consolidated financial statements, on November 30, 2023, the Company completed the acquisition of Noveprim, resulting in a 90% controlling interest. Of the acquired long-term assets, $167.8 million of biological assets were recorded. The determination of the fair value of biological assets requires the use of significant judgment using management’s best estimates of inputs and assumptions that a market participant would use. To determine the fair value, management utilized the multiple period excess earnings model, which relies on the following key assumptions: projections of cash flows from the acquired entities, which includes future revenue, cost of revenue, operating income margins, and productivity rates, as well as the discount rate based on market participant’s weighted average cost of capital.

The principal considerations for our determination that performing procedures relating to the valuation of biological assets acquired in the acquisition of Noveprim is a critical audit matter are (i) the significant judgment by management when developing the fair value estimate of the biological assets acquired; (ii) a high degree of auditor judgment, subjectivity and effort in performing procedures and evaluating management’s significant assumptions related to the cost of revenue, productivity rates, and discount rate; and (iii) the audit effort involved the use of professionals with specialized skill and knowledge.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to the acquisition accounting, including controls over management’s valuation of the biological assets acquired. These procedures also included, among others (i) reading the purchase agreement; (ii) testing management’s process for developing the fair value estimate of the biological assets acquired; (iii) evaluating the appropriateness of the multiple period excess earnings model; (iv) testing the completeness and accuracy of the underlying data used in the multiple period excess earnings model; and (v) evaluating the reasonableness of the significant assumptions used by management related to the cost of revenue, productivity rates, and discount rate. Evaluating management’s assumptions related to the cost of revenue and productivity rates involved considering (i) the past performance of Noveprim; (ii) the consistency with external research data; and (iii) whether the assumptions were consistent with evidence obtained in other areas of the audit. Professionals with specialized skill and knowledge were used to assist in evaluating (i) the appropriateness of the multiple period excess earnings model and (ii) the reasonableness of the discount rate assumption.

Discovery and Safety Assessment Service Revenue Recognized Over Time Using the Input Method

As described in Notes 1 and 3 to the consolidated financial statements, the Company recognized Discovery and Safety Assessment (DSA) revenue from services and products transferred over time of $2,611.6 million for the year-ended December 30, 2023, of which the majority relates to services that are delivered to the customer based on the extent of progress towards completion of the performance obligation that management measures using the cost-to-cost (input method). Management uses the input method measure of progress when it best depicts the transfer of value to the customer, which occurs as the Company incurs costs on its contract, generally related to fixed fee service contracts. Under the input method measure of progress, the extent of progress towards completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation. The cost calculation includes variables such as labor hours, allocation of overhead costs, research model costs, and subcontractor costs. Revenue is recorded proportionally as costs are incurred.

The principal considerations for our determination that performing procedures relating to DSA service revenue recognized over time using the input method is a critical audit matter are a high degree of auditor subjectivity and effort in performing procedures and evaluating audit evidence related to the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to DSA service revenue recognized over time using the input method, including controls over the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation, review of contracts, testing of budget versus actual costs incurred, and testing of revenue recognition. These procedures also included, among others (i) reading contracts and reports describing the results of services provided for a sample of DSA service contracts; (ii) testing management’s process for determining the amount of DSA service revenue recognized over time for a sample of DSA service contracts; (iii) evaluating the appropriateness of the input method used by management; (iv) evaluating the reasonableness of the ratio of costs incurred to date to the total estimated costs at completion of the performance obligations through performing a retrospective comparison of actual costs incurred to historical estimated costs for completed service contracts; and (v) testing actual costs incurred for a sample of in-progress service contracts by examining evidence of costs incurred.

/s/PricewaterhouseCoopers LLP

Boston, Massachusetts

February 14, 2024

We have served as the Company’s auditor since 1999.