Charles River Laboratories International Inc

Item 1A. Risk Factors

In addition to the other information set forth in this report, you should carefully consider the factors discussed in Part I, Item 1A. Risk Factors in our Annual Report on Form 10-K for fiscal year 2024, which could materially affect our business, financial condition, and/or future results. The risks described in our Annual Report on Form 10-K are not the only risks we face. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial also may materially adversely affect our business, financial condition, and/or operating results. There have been no material changes to the risk factors set forth in our Annual Report on Form 10-K for fiscal year 2024 as filed with the SEC on February 19, 2025, except as disclosed below.

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Significant developments or changes in national laws or policies to protect or promote domestic interests and/or address foreign competition can have an adverse effect on our business and financial statements.

Significant developments or changes in national laws or policies to protect or promote domestic interests and/or address foreign competition, including laws and policies in areas such as trade, manufacturing, government purchasing, healthcare, intellectual property, regulatory enforcement and investment/development, can adversely affect our business and financial statements. The U.S. has experienced a rapid increase in new government regulations, including tariffs and proposed tariffs on imports from a wide range of markets and geographies, including some in which we operate. These tariffs/proposed tariffs have prompted retaliatory tariffs by a number of countries and a cycle of retaliatory tariffs by both the U.S. and other countries. In early April 2025, actions were taken by the U.S. and certain other countries to delay the effective date of certain of these tariffs, but as of the date of this report a number of new tariffs remain in effect, including significant tariffs between the U.S. and countries from which we obtain significant supply, such as Vietnam, Mauritius, and China. Collectively, this may adversely impact our operating margin and results of operations, for example, our costs and expenses related to our business activities and those of our customers and suppliers; demand for our products and our competitive positioning; the availability to us of certain products in certain countries; and our supply chain operations. Please see Managements Discussion and Analysis of Financial Condition and Results of Operations for further discussion of the impact of these tariffs. Though the risks identified above in certain cases have already adversely impacted part of our business, the full impact of these tariffs and other actions on the Company and on our business partners remains highly uncertain and subject to rapid change.

A reduction or delay in government funding of RD may adversely affect our business.

A portion of revenue, predominantly in our RMS segment, is derived from clients at academic institutions and research laboratories whose funding is partially dependent on both the level and timing of funding from government sources such as the U.S. National Institutes of Health (NIH) and similar domestic and international agencies, which can be difficult to forecast. We also sell directly to the NIH and these other agencies. Government funding of RD is subject to the political process, which is inherently fluid and unpredictable. For example, the NIH announced on February 7, 2025, a policy significantly reducing research grants by limiting payments for indirect overhead. While, as of the date of this filing, the order is subject to a preliminary injunction, there can be no assurance that a permanent injunction will be granted or that other adverse actions will not be taken. Our revenue may be adversely affected if our clients delay purchases as a result of uncertainties surrounding the approval of government budget proposals, included reduced allocations to government agencies that fund RD activities. Government proposals to reduce or eliminate budgetary deficits have sometimes included reduced allocations to the NIH and other government agencies that fund RD activities, or NIH funding may not be directed towards projects and studies that require the use of our products and services, both of which could adversely affect our business and our financial results.

Changes in government regulation or in practices relating to the pharmaceutical or biotechnology industries, including potential healthcare reform, could decrease the need for the services we provide.

Governmental agencies throughout the world strictly regulate the drug development process. Our business involves helping our customers navigate these regulatory processes. Accordingly, many regulations, and often new regulations, are expected to result in higher regulatory standards and often additional revenues for companies that service these industries. However, some changes in regulations, such as a relaxation in regulatory requirements or the introduction of streamlined or expedited drug approval procedures, or an increase in regulatory requirements that we have difficulty satisfying or that make our services less competitive, could eliminate or substantially reduce the demand for our services.

For example: in December 2022, the FDA Modernization Act 2.0 was passed, which clarifies methods manufacturers and sponsors can use to investigate the safety and efficacy of a drug; and in April 2025 the FDA announced its intention to reduce animal testing in preclinical safety studies with scientifically validated cell-based and new approach methodologies (NAMs), such as organ-on-a-chip systems, computational modeling, and advanced in vitro assays. Eliminating the use of animals in research may have material adverse effects on our business, results of operations, or financial condition. While there have been significant advancements in the development of alternative methods, the complete elimination of animals in research will be a gradual process that may take many years to achieve. While we are committed to working with the industry to support

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development and to provide the best translational models to supplement or replace traditional models as part of our Replacement, Reduction, and Refinement (3Rs) initiative and our Alternative Methods Advancement Project (AMAP), the use of animals in research is highly regulated and proposed changes to current regulations will need to be carefully evaluated to ensure that they do not compromise the safety and efficacy of new drugs and medical treatments.

Although we believe we are currently in compliance in all material respects with applicable national, regional and local laws, as well as other accepted guidance used by oversight bodies (including the USDA, the standards set by the International Air Transport Association, the Convention on International Trade in Endangered Species of Wild Fauna and Flora, USFWS, The Centers for Disease Control, the Department of Transportation, the Department of State, the office of Laboratory Animal Welfare of NIH, the Drug Enforcement Agency, as well as numerous other oversight agencies in the jurisdictions in which we operate), failure to comply could subject us to denial of the right to conduct business, fines, criminal penalties and other

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enforcement actions. For additional discussion of the factors specifically affecting our non-human primates including related oversight trade compliance agencies, please see the sections entitled Item 1A. Risk Factors Industry Risk Factors - Several of our product and service offerings, including our non-human primate supply, are dependent on a limited source of supply that, when interrupted, adversely affects our business, included within our Annual Report on Form 10-K for fiscal year 2024 as filed with the SEC on February 19, 2025 and Item 1. Legal Proceedings above. In addition, if regulatory authorities were to mandate a significant reduction in safety assessment procedures that utilize research animals (as has been advocated by certain groups), certain segments of our business could be materially adversely affected.

Implementation of healthcare reform legislation, such as certain provisions of the Inflation Reduction Act, may have certain benefits, but also may contain costs that could limit the profits that can be made from the development of new drugs. This could adversely affect RD expenditures by pharmaceutical and biotechnology companies, which could in turn decrease the business opportunities available to us both in the U.S. and abroad. In addition, new laws or regulations may create a risk of liability, increase our costs or limit our service offerings. Furthermore, if health insurers were to change their practices with respect to reimbursements for pharmaceutical products, our clients may spend less or reduce their growth in spending on RD.

While it is not possible to predict whether and when any such changes will occur, changes at the local, state or federal level, or in laws and regulations in effect in foreign jurisdictions in which we operate or have business relationships, may significantly impact our domestic and foreign businesses and/or those of our clients. Furthermore, modifications to international trade policy, public company reporting requirements, environmental regulation and antitrust enforcement may have a materially adverse impact on us, our suppliers or our clients.

New technologies may be developed, validated and increasingly used in biomedical research, which could reduce demand for some of our products and services.

The scientific community continues to develop NAMs, which do not involve working with animal models and are designed to increase the translation from findings in early-stage discovery and pre-clinical studies to human studies, and vice-versa. As these methods continue to advance, they may supplement, and in some cases possibly replace or supplant methodologies that are currently in use, such as the use of traditional living animals in biomedical research. For example, in April 2025, the FDA announced its intention to reduce animal testing in preclinical safety studies with NAMs, such as organ-on-a-chip systems, computational modeling, and advanced in vitro assays. In addition, technological improvements, such as imaging and other translational biomarker technologies, could impact demand for animal research models. Further, manufacturers, including Charles River, have recently introduced recombinant versions of LAL, which has been historically derived from live animals. It is our strategy to explore new technologies to refine and potentially reduce the use of animal models and animal derived products as new in vitro and in silico methods become available and synthetically-manufactured products become validated with sufficient data to ensure public safety. For information regarding our efforts to support development and to provide the best translational models to supplement or replace traditional models, see Our Strategy included within our Annual Report on Form 10-K for fiscal year 2024 as filed with the SEC on February 19, 2025. However, we may not be able to develop new products, inputs or processes effectively or in a timely manner to replace any lost sales. Lastly, other companies or entities may develop research models, inputs or processes with characteristics different from those that we produce, and that may be viewed as more desirable by some of our clients.

Our quarterly operating results may vary, which could negatively affect the market price of our common stock.

Our results of operations in any quarter may vary from quarter to quarter and are influenced by the risks discussed above, as well as: changes in the general global economy; changes in the mix of our products and services; changes in government regulation or in practices related to the pharmaceutical or biotechnology industries, including with respect to the use of NAMs; cyclical buying patterns of our clients; the financial performance of our strategic and venture capital investments; certain acquisition-related adjustments, including change in fair value of contingent payments both receivable from or payable to counterparties; and the occasional extra week (53rd week) that we recognize in a fiscal year (and fourth fiscal quarter thereof), including 2022, due to our fiscal year ending on the last Saturday in December. We believe that operating results for

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any particular quarter are not necessarily a meaningful indication of future results. Nonetheless, fluctuations in our quarterly operating results could negatively affect the market price of our common stock.

Our review of potential strategic alternatives may not result in an executed or consummated transaction or other strategic alternative, and the process of reviewing strategic alternatives or the outcome could adversely affect our business.

On May 6, 2025, in connection with a Cooperation Agreement entered into with a large shareholder of the Company, we agreed, among other things, to have the Strategic Partnership and Capital Allocation Committee of our Board of Directors oversee and direct a comprehensive strategic review and evaluation of the Companys business and prospects, including an examination of various alternatives to enhance long-term stockholder value. There is no assurance that the process will result in the approval or completion of any specific transaction or outcome. Further, there is no guarantee that any transaction resulting from the strategic review will ultimately benefit our stockholders. 

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The process of reviewing potential strategic and operational alternatives is time consuming and costly and may divert managements attention. It may also be disruptive to our business operations and long-term planning, which may cause concern to our current or potential investors, customers, employees, strategic partners, vendors and other stakeholders and may have a material impact on our operating results or result in increased volatility in our stock price.

Any potential transaction or other strategic alternative would be dependent on a number of factors that may be beyond our control, including, among other things, market conditions, industry trends, regulatory approvals, and the availability of financing for a potential transaction on favorable terms. There can be no assurance that any potential transaction or other strategic alternative will be successfully implemented, achieve the intended benefits or provide greater value to our stockholders than that reflected in the current price of our common stock. Until the review process is concluded, perceived uncertainties related to our future may result in the loss of potential business opportunities, volatility in the market price of our common stock and difficulty attracting and retaining qualified talent and business partners.