QUEST DIAGNOSTICS INC (DGX) Business

Item 1. Business

INTRODUCTION

Quest Diagnostics works across the healthcare ecosystem to create a healthier world, one life at a time. We provide diagnostic insights from the results of our laboratory testing to empower people, physicians, and organizations to take action to improve health outcomes. Derived from one of the world's largest databases of de-identifiable clinical lab results, our diagnostic insights reveal new avenues to identify and treat disease, inspire healthy behaviors and improve healthcare management. In the right hands and with the right context, our diagnostic insights can inspire actions that transform lives and create a healthier world.

The patients we serve annually comprise approximately one-third of the adult population of the United States, and over a three-year period, we serve approximately one-half of the adult population of the United States. We estimate that annually we serve approximately half of the physicians and half of the hospitals in the United States.

The Quest Way

We operate our business and achieve our goals according to a clear set of principles we call “The Quest Way,” which consists of the following:

•Our Purpose, or why we exist, is to work together to create a healthier world, one life at a time.

•Our Strategy, or how we grow, is to provide solutions that serve the evolving needs of our customers, based on our high quality, innovative, convenient and affordable services.

•Our Culture, or how we work, is powered by what we call the “5Cs”: customer first, collaboration, care, continuous improvement, and curiosity.

We play a critical role in healthcare decisions for customers across the healthcare ecosystem, including physicians, hospitals, patients and consumers, health plans, government agencies, employers, retailers, pharmaceutical companies and insurers. We believe The Quest Way is aligned with the triple aim of healthcare of improving medical quality and the patient experience while reducing the overall cost of care.

We believe our employees are critical to our success, and we continually strive to create an environment that allows them to contribute to our goal of creating a healthier world. We are focused on delivering services that help improve the physician and healthcare provider experience to enable us and them to deliver high quality, effective and affordable care to patients. We provide a number of innovative ways for patients to access services from us, including consumer-initiated services offered through QuestHealth.com, which provides a high quality, self-directed option with physician oversight for individuals to gain insights into their health.

During 2025, we generated net revenues of $11.0 billion. Additional financial information concerning Quest Diagnostics for each of the years ended December 31, 2025, 2024 and 2023 is included in “Management's Discussion and Analysis of Financial Condition and Results of Operations” in Part II, Item 7 and our consolidated financial statements and notes thereto in “Financial Statements and Supplementary Data” in Part II, Item 8.

Quest Diagnostics was incorporated in Delaware in 1990; its predecessor companies date back to 1967. We conduct business through our headquarters in Secaucus, New Jersey, and our laboratories, patient service centers, offices and other facilities around the United States and in selected locations outside the United States. Unless the context otherwise requires, the terms “Quest Diagnostics,” “Quest,” the “Company,” “we” and “our” mean Quest Diagnostics Incorporated and its consolidated subsidiaries.

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OUR STRATEGY

Our strategy aims to achieve two key goals: generate growth and optimize our operating efficiency. Our growth strategy focuses on continually developing solutions to meet the evolving needs of our customers. We help people make the best decisions to improve health by providing high quality, innovative, convenient and affordable diagnostic testing insights and services using our scale and extensive reach. We drive growth by:

•offering an industry-leading menu of testing and other services;

•collaborating with healthcare providers and partners to leverage our broad access;

•leveraging our data assets and services to improve population health and enable value-based care; and

•continuously improving our quality and efficiency by leveraging the Quest Management System and by embracing innovative technologies, such as automation and artificial intelligence ("AI").

Our growth strategy is focused on our primary customer channels – physicians, hospitals, patients and consumers – supported by Advanced Diagnostics™ (defined below), strategic acquisitions, and continuous quality improvement.

Physicians

We serve approximately half the physicians in the United States each year. We serve virtually all types of physicians from primary care physicians and internists to specialists, including rheumatologists, cardiologists, neurologists, and obstetricians/gynecologists. We also serve physicians associated with accountable care organizations (“ACOs”), and Federally Qualified Health Centers (“FQHCs”). Physicians determine which laboratory to recommend or use based on a variety of factors, but we believe that we provide the most attractive service offering in the industry, including a comprehensive test menu, innovative test offerings, a positive customer experience, deep medical and scientific expertise, high quality, leading access and distribution, and data-powered integrated information-technology solutions. Large physician practices value our ability to standardize services on a national or regional scale.

Hospitals

We believe that the market challenges faced by hospitals, including continued consolidation, price transparency, cost and utilization pressure, evolving healthcare payment models, capital needs, changing technology and limited resources, provide us with an opportunity to partner with them as they consider more effective ways to implement their laboratory testing strategy and drive demand for our expertise and services.

We serve approximately half the hospitals in the United States each year in many ways, including:

•Serving as a hospital lab’s laboratory. In 2025, we generated approximately $1.2 billion in revenue from “reference testing,” where we perform testing that hospitals do not perform in their own in-hospital labs.

•Helping hospitals operate their labs more efficiently. In 2025, our Collaborative Lab Solutions (formerly known as Professional Laboratory Services) offering generated approximately $800 million in revenues and management fees supporting hospitals in the operation of their own labs. Our key Collaborative Lab Solutions offerings include lab management outsourcing, test menu optimization and spend consolidation, supply chain management, and providing advanced data solutions.

•Acquiring outreach lab operations from hospitals. Quest looks for opportunities to acquire assets of outreach lab operations from hospitals whose in-house labs have expanded from supporting in-patients to supporting out-patients and ambulatory patients who see physicians that may or may not be employed or otherwise affiliated with the hospitals.

We also have joint venture arrangements with leading hospitals and health systems. These joint venture arrangements, which provide diagnostic information services for affiliated and nonaffiliated hospitals and clinicians and other local healthcare providers, serve as our principal facilities in their service areas. Typically, we have either a majority ownership interest in, or day-to-day management responsibilities for, our joint venture relationships.

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Patients and Consumers

We have taken steps to be recognized as the consumer-friendly provider of choice of diagnostic information services. Patients increasingly expect their healthcare experiences to be consumer-centric, which includes being more transparent, accessible and convenient. Most patients have a choice when selecting a diagnostic testing provider, and our goal is to provide leading services in conveniently located patient service centers that can provide a comprehensive suite of testing services. Many of our 2,400 patient service centers are located inside large retail stores or in convenient retail settings. We continue to enhance our operations to improve the patient experience in these locations. For example, our "Schedule at Check In" capability encourages patients to make appointments, including through mobile appointment scheduling, and our self-serve kiosks provide wait-time estimates for walk-in and standby patients and offer many language options. These improvements allow us to better manage demand and productivity and have reduced average wait times in the patient service centers. We also provide mobile phlebotomy services in many parts of the United States so patients who prefer an in-home blood draw may access our services for a fee.

We work to improve our digital experience, from making it easier for patients and consumers to locate a patient service center and receive results on our MyQuest® patient healthcare portal to enabling providers to access their patients’ test result reports. We are also integrating the patient payment process into the digital customer experience, which improves the patient experience, provides greater pricing transparency, helps our patient concession rate and reduces demands on phlebotomists.

As consumers increasingly seek more involvement and control over their health and wellness, we aim to meet them where they are. Our QuestHealth.com platform empowers health- and wellness-minded consumers to purchase tests and panels without the need to schedule an appointment and visit a doctor’s office. Through this platform, we enable access to third-party physician review to place test orders and be available to consult with the consumer via a teleconsult about their test results. We offer over 150 tests, including comprehensive wellness panels with up to 85 key health indicators, tests to monitor certain chronic conditions, and tests for students and workers in healthcare, education and other occupations that require them. Our cash pay price for consumers is convenient for those who wish to establish their baseline wellness status, monitor themselves for chronic medical conditions, and are interested in their wellness throughout relevant time periods, such as athletes preparing for events. We are also powering the testing offered by leading health, wellness, and wearable brands, where we provide the underlying testing services for their consumer health service offerings. Our multi-channel consumer offerings reflect our belief that our consumer focus positions us to capture expanding opportunities presented by the growth of consumer-initiated testing and of the demand for expanded access to health and wellness services.

We continually evaluate technologies with the potential to improve choice and convenience for patients and consumers. We offer patients and consumers experiencing symptoms of several common genital tract infections, including sexually transmitted infections, the option to self-collect a swab specimen, aimed at increasing privacy, convenience and speed of testing. In 2025, we introduced specimen self-collection in clinical settings for human papillomavirus (HPV) screening to help identify women at risk for developing cervical cancer, broadening access to a vital preventative care test. We also provide opportunities for companies with telehealth and retail business models to rebrand our testing and utilize our patient service centers to provide access.

Other Customer Channels

Our other customer channels include health plans, employers, new and emerging retail healthcare providers, government agencies, pharmaceutical companies and other commercial clinical laboratories, which are described in more detail under “ – Customer Channels.” While we principally focus on the U.S. market, we serve customers globally and have a growing business that provides advanced reference testing to laboratory providers in other countries. For more information about our operations, see “ – Business Operations.”

Advanced Diagnostics

We support the needs of all our customers with a focus on Advanced Diagnostics™. Clinical laboratory testing can be characterized as routine, non-routine or advanced. Non-routine tests (commonly referred to as esoteric) are tests that may require professional “hands-on” attention from highly-skilled technical personnel, generally require more sophisticated data analysis, technology, equipment or materials, may be performed less frequently than routine tests and may be reimbursed at higher levels than routine tests. We refer to certain non-routine, highly innovative and specialized tests that we offer as Advanced Diagnostics™.

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We are a leading provider of Advanced Diagnostics™ and provide an array of offerings, including certain procedures in the areas of molecular diagnostics (including next-generation sequencing), oncology, neurology, companion diagnostics and non-invasive pre-natal and other germline genetic testing. In 2025, certain Advanced Diagnostics™ test offerings within five clinical areas – oncology, cardiometabolic and endocrine, brain health, autoimmune, women’s health and genetics – generated over $1 billion in revenues on double-digit revenue growth.

Our investments in our Advanced Diagnostics™ offerings enhance our innovation capabilities and strengthen our service offering, making our Advanced Diagnostics™ offerings more attractive and accessible to physicians and hospitals. We are also applying the capabilities gained by these efforts to support other areas where we can make a meaningful difference in healthcare, including offerings to pharmaceutical companies and consumers.

We are also particularly focused on the rapidly growing areas of monitoring recurrence and therapy effectiveness. In 2023, we acquired Haystack Oncology, Inc. ("Haystack Oncology") a cancer testing company that has developed a highly sensitive testing technology for detecting minimal-residual disease (“MRD”) by circulating tumor DNA due to residual or recurring cancer. Circulating tumor DNA ("ctDNA") refers to DNA fragments shed by a solid tumor, such as colorectal or breast cancer, into the blood stream. We believe this acquisition strengthens our comprehensive oncology portfolio by positioning us well to compete in the higher-growth clinical area of ctDNA solid-tumor MRD testing. Since the acquisition, several organizations have used the Haystack Oncology MRD test in research, including for clinical trials. In 2025, we received a breakthrough device designation from the U.S. Food and Drug Administration (“FDA”) for our Haystack Oncology MRD test for patients with an early stage colorectal cancer diagnosis. This milestone reinforces the high caliber of our cancer monitoring innovation by validating the use of the Haystack Oncology MRD test and opens avenues for developing companion diagnostics. We continue to make progress towards commercialization by expanding access. In 2025, we commenced separate trials with Mass General Brigham and Rutgers Cancer Institute to further research Haystack Oncology MRD test's clinical utility as a guide in making post-operative therapy decisions.

We also continue to focus on neurology. In 2023, we launched our QUEST AD-Detect® test portfolio for assessing Alzheimer's disease risk using blood specimens, as opposed to testing by more costly or invasive methods, such as testing of cerebral spinal fluid by lumbar puncture. We continue to publish evidence on our AD-Detect test, including a study in a publication of the American Academy of Neurology that found two of our innovative panels provide confirmatory accuracy for aiding Alzheimer's diagnosis. We continue to add new testing to this suite of services for assessing the risk of Alzheimer's Disease, including isoform and plasma testing for patients with cognitive impairment. In addition, our Autoimmune ANAlyzeR™ service helps primary care physicians comprehensively screen for autoimmune disorders to accelerate diagnosis and care by specialists.

Acquisitions and Capital Deployment

Our strategy includes generating growth through value-creating, strategically aligned acquisitions using disciplined investment criteria. We screen potential acquisitions using guidelines that assess strategic fit and financial considerations, including value creation, return on invested capital and impact on our earnings. We endeavor to grow revenues each year by 1-2% through acquisitions. We will continue to invest in our business in a disciplined manner, including focusing on enhancing our solid foundation of strategic assets and capabilities. In 2025, we acquired select clinical testing and dialysis-related water testing assets of Fresenius Medical Care's wholly-owned Spectra Laboratories, a leading provider of renal-specific laboratory testing services in the United States. We also entered into a joint venture with Corewell Health, a leading health system in Michigan, which will perform laboratory testing in the state of Michigan via a new laboratory facility. Equity ownership of the joint venture is shared 51% by Quest and 49% by Corewell Health. In addition, we provide the full complement of our Collaborative Lab Solutions offering for Corewell Health.

Our significant acquisitions in each of the last three years are further discussed in Note 6 to the audited consolidated financial statements (Part II, Item 8 of this Report).

Acquisitions are part of our disciplined capital deployment framework, which also includes investment in our business, dividends and share repurchases and is grounded in maintaining an investment grade credit rating. We expect to return a majority of our free cash flow to stockholders through a combination of dividends and share repurchases over time. Consistent with that expectation, in February 2026, we announced that we increased our quarterly common stock cash dividend by approximately 7.5%, from $0.80 per common share to $0.86 per common share. This represents our 15th increase in the dividend since the beginning of 2012. For many years, we have maintained a common stock repurchase program. Since the beginning of 2012, we have returned approximately $8.1 billion to stockholders through repurchases of our common stock.

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OUR STRENGTHS

Continuous Quality Improvement

Our goal is to provide every patient and customer with services and products of superior quality. We strive to accomplish that through rigorous processes that we measure and seek to improve, and by using the Quest Management System, which provides best-in-class business performance tools to create and implement effective and sustainable quality processes. Our Quality and Regulatory Affairs organization continues to advance our commitment to operational excellence, regulatory integrity, and a culture of quality. Our Quality Program includes policies and procedures to document, measure and monitor the effectiveness of our laboratory operations in providing and improving quality and meeting applicable regulatory requirements. The Quality Program is designed so that the quality of laboratory services is monitored objectively and evaluated systematically to deliver superior quality care, identify opportunities to improve patient care and resolve identified problems.

Recently, we enhanced enterprise engagement through a unified Quality Policy and advanced our quality foundation by refining global processes, updating our Quality Framework, and deepening our cross-site collaboration. Additionally, we have a robust Supplier Quality Program designed to help us ensure we have a high-quality supplier network and to raise the bar of quality expectations across that network.

Operating Efficiency

We strive to enhance operational excellence and improve our efficiency across our value chain and operations, from the time that we first interact with a potential customer until the time we receive payment for our services. Improving our operations through standardization, optimization, digitization and automation can yield many benefits, including improving our quality and competitiveness, strengthening our foundation for growth, supporting our growth strategy, and increasing employee engagement, customer service and shareholder value. We are guided by a service dashboard that focuses throughout our operations on quality for consumers, healthcare providers and employees, including medical quality, on-time delivery, and employee safety.

Our cost excellence program, Invigorate, includes structured plans to drive savings and improve productivity across the value chain, including in such areas as patient services, logistics and laboratory operations, revenue services, information technology ("IT") and procurement. Our Invigorate program has consistently delivered 3% of annual cost savings and productivity improvements, which partly offset pressures from an inflationary environment, including labor and benefit cost increases, and reimbursement pressures. We are leveraging automation and AI to improve quality and productivity across our entire value chain, not just in the laboratory. For example, we advanced our use of automation in front-end specimen processing and labeling in six of our labs, freeing more of our processors to focus on higher-order work. We also completed a successful pilot of our automated specimen processing and labeling platform at our Clifton, NJ lab. In 2025, we initiated or expanded our use of AI and automation in several areas, ranging from digital cytology, microbiology, parasitology and digital pathology. Other areas of focus include reducing denials and patient concessions, logistics route optimization to speed specimen transport, and enhancing the digital experience.

In February 2025, we committed to a multi-year project ("Project Nova") to modernize our "Order to Cash" business processes, which includes the related information technology infrastructure and underlying enabling technologies. We are partnering with Epic, a third-party licensor, to assist in the implementation of Project Nova. We expect to deliver value throughout the implementation of Project Nova, which is expected to be completed in 2031 to 2032, as it unlocks a variety of streamlined operational benefits, reduced technology-related operating costs, accelerated revenue opportunities, and improvements to the customer and patient experience.

Organized to Drive Growth and Value

We strive to strengthen our organizational capabilities to align around growth opportunities, coordinate business units for seamless execution and leverage our company-wide infrastructure to gain more capability, value and efficiency. The value creation side of our business includes product and commercial marketing and is organized by clinical franchise and focuses on customer solutions for the marketplace, including new test development and diagnostic insights. Our clinical franchises – Cardiometabolic, Endocrine, and Wellness, Drug Monitoring and Toxicology, Infectious Diseases and Immunology, Molecular Genomics and Oncology, Neurology, and Women’s and Reproductive Health – enable us to operate like a boutique laboratory while maintaining our scale advantages, and work with our research and development and commercial organizations to identify and deliver new and improved solutions. The value delivery side includes sales, laboratory operations, field operations, logistics and client services.

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Assets and Capabilities that Deliver Value

We collaborate with partners and customers across the healthcare ecosystem to help create a healthier world. The table below outlines some of the assets and capabilities that make us an attractive partner.

Strong Relationships with Health Plans and Other Payers

Most of the services we perform are paid for by third-party payers, including large national health plans, regional and local health plans and government payers, which includes Medicare and Medicaid. Through these payers, we estimate that we have access to over 90% of insured lives in the United States. We work with payers to reduce the cost of care, improve the customer experience and drive better outcomes for patients. We can strengthen our relationships with health plans and increase the volume of our services for their members by focusing on driving value and providing strong value propositions for members and physicians. For example, we build information platforms to help health plans manage utilization and population health, keep laboratory testing in network and provide an alternative to high-cost labs. We also offer extended care services to help close gaps in care designed to be attractive to payers.

Medical and Scientific Expertise

We leverage our medical and scientific expertise and aspire to be a trusted authority in diagnostic medicine, provide insights and tools to support public and personal health, lead and facilitate scientific discussion and inspire innovation. Our medical and scientific experts regularly provide presentations, symposia and webinars regarding diagnostic testing and participate on scientific committees determining guidelines for diagnostic usage. They also publish research that demonstrates the clinical value and importance of diagnostic testing, including in connection with our research and development efforts, in peer-reviewed journals, textbooks and other publications. For over 30 years, the Company has published the Quest Diagnostics® Drug Testing Index,TM a series of reports on national workplace drug positivity trends based on the Company's employer workplace drug testing data, that is widely cited by employers, the federal government and the media to help identify and quantify drug abuse among the nation's workforce. The Company also publishes Quest Diagnostics® Health Trends,® scientific reports that provide insights into health topics, based on analysis of objective clinical laboratory data, to empower better patient care, population health management and public health policy. In 2025, we published a Health Trends® report showing that many oncologists feel they are seeing more patients with advanced cancers due to screening barriers, such as

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missed or delayed follow-up care or monitoring, and that imaging tests may not detect cancer recurrence early enough. Many of these oncologists believe that ctDNA MRD testing could reduce diagnosis delays in cancer recurrence.

We are a founding member, with other leading diagnostic laboratories outside the United States, of the Global Diagnostics NetworkTM, a strategic working group of diagnostic laboratories committed to unleashing and sharing local innovation to increase global access to diagnostic science, information and services and generating enhanced diagnostic insights to improve the delivery of global healthcare.

Health Information Technology Solutions and Information Assets

We have a history of providing leading IT for diagnostic information services, including for patients, physicians and healthcare organizations. We were the first national diagnostic information services provider to offer online patient appointment scheduling and a patient connectivity solution. Our MyQuest® patient healthcare portal, with more than 45 million registered users at year-end 2025, enables patients to manage healthcare and medical information for themselves and a circle of others, find a Quest Diagnostics location, schedule appointments, receive appointment reminders, assess whether their health plan is in-network and receive and archive their test results. Individuals can also use their smartphone or computer to order a consumer-initiated test from us at QuestHealth.com. Our connectivity platform enables providers to easily order tests and receive results from us from more than 1,000 electronic health records systems. We are expanding our use of digital and other technology tools to improve our customer experience for patients and providers.

We also have significant information assets and offer a robust portfolio of powerful analytics that inspire action and deliver value to our customers. We offer an array of solutions based on data insights, including retrospective analytics solutions for physicians, hospitals, health plans, pharmaceutical companies and public health organizations. We believe these solutions can tap the potential of large amounts of clinical information to: enhance the customer experience; deliver more precise, comprehensive solutions and actionable information; provide increased and interactive insights and analytics; foster greater adherence to clinical and reimbursement guidelines; and advance the development of precision medicine. We believe that the breadth and depth of our data, combined with our powerful analytics capabilities, enables us to take advantage of important data-based opportunities in diagnostics, and provides us a competitive advantage.

Innovation

We are a leading provider of innovation in diagnostic information services that help healthcare market participants care for their patients through better testing for predisposition, screening, monitoring, diagnosis, prognosis and treatment choices, and that can deliver high clinical value to the medical community and reduce the overall cost of healthcare. We develop and introduce new tests through our research and development operations. Our capabilities include discovery, technology development and clinical validation of diagnostic tests. We also partner with other developers of new technologies, services and tests to transfer their innovations to the marketplace, using our in-house expertise (e.g., strength in new service development and commercialization of testing services). These developers include large commercial manufacturers, the academic community, pharmaceutical and biotechnology firms, emerging medical technology companies, other laboratory companies and others that develop and commercialize novel diagnostics, pharmaceutical and device technologies. Given our expertise and broad U.S. network, we believe we are the distribution channel of choice for developers of new diagnostic information solutions. Our innovation strategy focuses on new services and solutions for unmet clinical needs that will improve patient care and outcomes as well as economic value for patients, health plans and other payers. In 2023 and 2025, certain diagnostic programs received FDA Breakthrough Device Designation, designed to address identified limitations in current diagnostic methodologies and unmet clinical needs.

Our research and development team includes leaders in a number of fields, including genomics, genetics and bioinformatics, as well as in disease states, such as oncology, neurology, cardiometabolic disease and other disorders. We are also well positioned to take advantage of advances in next generation sequencing to grow our business in cancer and other disease state testing. This includes inherited genetics, newborn screening, rare disease diagnosis, and solid tumor sequencing, such as to aid treatment selection and monitoring. We also maintain relationships with advisers and consultants who are leaders in key fields of science and medicine who advise us with our internal team of experts, complementing our expertise.

We endeavor to improve test processes, including through increased automation and AI. For example, we provide automated next generation genetic sequencing, which will enable genetic screening that is more precise, faster and at lower cost. In addition, we aim to develop holistic solutions responsive to challenges that healthcare providers and patients face, by developing solutions of tests, information and services focused on specific clinical challenges. We look to offer solutions from our large dataset and data analytics capabilities to help providers and health plans identify opportunities to optimize appropriate

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laboratory utilization, align clinical practice to medical guidelines, and inform patient-care decisions. We also look for innovations and solutions that are more convenient, less invasive and more cost effective than currently available options.

We seek innovation in the ways we bring solutions directly to customers to allow them to be more involved in and have more control over their health outcomes, and to improve the customer experience, including enhanced services and end-to-end solutions for convenience and support.

Artificial Intelligence

We have a long history of using advanced technologies to automate processes, improve customer service and productivity, generate insights from lab and other data, improve the customer experience, and stimulate innovation. Other areas of focus include reducing denials and patient concessions, and logistics route optimization to speed specimen transport. We use AI to help drive innovation and operational efficiency through improving the quality of our screening and diagnostic capabilities. We also continue to broaden our use of AI in customer service to help our representatives access answers more quickly, improving their effectiveness and service quality. In 2025, we announced a collaboration with Google to use Google Cloud's data analytics and generative AI to help us streamline our data management, improve data analytics, and personalize the experiences we deliver to patients, providers, and other customers.

We are committed to using AI in an ethical, responsible and compliant way. We have implemented a formal AI governance oversight committee and established multiple AI safeguards to minimize risks associated with AI, including, but not limited to, expanded security and privacy measures, increased user access controls, employee and other end user training and certification, and standard operating procedures. Our AI program has been designed to comply with applicable laws, regulations and AI frameworks, and we strategically partner with external AI experts as needed to ensure we remain informed about the latest technological advancements and best practices in the industry. Over time, we believe AI, including generative AI, will help us innovate and grow in a responsible manner while also enhancing customer and employee experiences and bring operating and cost efficiencies. We intend to be at the forefront of the innovative, responsible and secure use of AI in diagnostic information solutions.

A Commitment to Improving Health and Well-Being in the Communities We Serve

As part of our commitment to creating a healthier world, we work alongside the Quest Diagnostics Foundation to support community-led solutions that seek to improve health and well-being in the communities we serve. Our approach leverages donated diagnostic testing by Quest and emphasizes investments in nonprofit healthcare systems, safety net providers, and community-based organizations addressing social drivers of health that create barriers to care. We have invested approximately $53 million to community initiatives across the United States and Puerto Rico. These investments span a broad range of evidence-based strategies, including community workforce development, community health worker care coordination models, expanded access to diagnostic testing, wellness and screening events, and education programs that promote long-term health and prevention. As we look ahead, we will continue to invest in evidence-based, scalable practices that improve health in the communities we serve.

BUSINESS OPERATIONS

The Company is made up of two businesses: Diagnostic Information Services and Diagnostic Solutions. Our Diagnostic Information Services business develops and delivers diagnostic information services, providing insights from the results of our laboratory testing to empower people, physicians, and organizations to take action to improve health outcomes. Our Diagnostic Solutions group includes our risk assessment services business, which offers solutions for insurers, and our healthcare IT businesses, which offers solutions for healthcare providers and payers. Our services primarily are provided under the Quest Diagnostics brand, but we also provide services under other brands, including AmeriPath,® Dermpath Diagnostics,® ExamOne,® and Quanum.®

We are a leading provider of diagnostic information services in the United States, where we conduct substantially all of our business. We see opportunities to bring our experience and expertise in diagnostic information services to markets outside the United States, including leveraging existing facilities to serve new markets.

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Diagnostic Information Services

Background - clinical testing. Clinical testing is an essential element in the delivery of healthcare services. Clinical testing is used for predisposition, screening, diagnosis, prognosis, monitoring, and treatment choices of diseases and other medical conditions. Clinical testing is generally categorized as clinical laboratory testing and anatomic pathology services.

Clinical laboratory testing, which can be characterized as routine, non-routine or advanced, generally is performed on whole blood, serum, plasma and other body fluids, such as urine, and specimens, such as microbiology samples. Clinical laboratory tests which can be performed by most clinical laboratories are considered routine. Routine testing measures various important bodily health parameters such as the functions of the kidney, heart, liver, thyroid and other organs. Commonly ordered routine tests include blood chemistries, urinalysis, allergy tests and complete blood cell counts. We also have a portfolio of oncology tests that includes traditional oncology screening and anatomic pathology, such as cervical cancer and skin cancer screening and diagnosis. Non-routine tests (commonly referred to as esoteric) may require professional “hands-on” attention from highly-skilled technical personnel, generally require more sophisticated data analysis, technology, equipment or materials, may be performed less frequently than routine tests and may be reimbursed at higher levels than routine tests. It may not be practical, from a cost-effectiveness or infrastructure perspective, for many hospitals, ACOs, commercial laboratories or physician office laboratories to develop and perform a broad menu of non-routine tests or to perform low-volume non-routine testing in-house. Such tests generally are outsourced to a clinical testing laboratory that can perform these non-routine tests. Some non-routine tests are Advanced Diagnostics™, which includes certain procedures in the areas of molecular diagnostics (including next-generation sequencing), oncology, neurology, companion diagnostics and non-invasive pre-natal and other germline genetic testing.

Anatomic pathology involves the diagnosis of cancer and other diseases and medical conditions through examination of tissue and cell samples taken from patients.

Our services. We primarily provide information and insights based on an industry-leading menu of routine, non-routine and advanced clinical testing and anatomic pathology testing, and other diagnostic information services. We have strong testing capabilities, including services for the predisposition, diagnosis, treatment and monitoring of cancers and other diseases, and offer advanced tests in many fields, including endocrinology, immunology, neurology and oncology. Increasingly, we are focused on providing solutions and insights to our customers, based on the testing that we perform, the data that we gather and our extensive medical, information and connectivity assets. We believe that offering services, solutions and insights based on a full range of tests, information assets and other capabilities strengthens our market offering, market position and reputation.

We offer broad access to clinical testing through a network of laboratories, including advanced laboratories as well as rapid response laboratories (smaller facilities where we can quickly perform an abbreviated menu of routine tests for customers that require rapid turnaround times). We operate 24 hours a day, 365 days a year. Our network also includes patient service centers, phlebotomists in physician offices, and our connectivity resources, including call centers and mobile phlebotomists, nurses and other health and wellness professionals. Our large in-house staff of medical and scientific experts, including medical directors, scientific directors, genetic counselors and board-certified geneticists, provide medical and scientific consultation to healthcare providers and patients regarding our tests and test results, and help them best utilize our services to improve outcomes and enhance satisfaction. We also provide testing (including anatomic pathology) services and medical director services at hospital laboratories.

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We are a leading provider of diagnostic information services, developing and delivering comprehensive offerings to help physicians manage patients across disease stages, from screening for early risk to treatment selection and monitoring to post-treatment evaluation. We have comprehensive test offerings in cardiometabolic and endocrine; cancer; clinical drug monitoring and toxicology; infectious disease, including autoimmune; neurology diagnostics, including Alzheimer’s disease; and women’s health, including prenatal genetics. We strive to provide diagnostic solutions for emerging infectious diseases, and were the first commercial laboratory to introduce a test for the H5 avian flu virus based on a preparedness contract from the Centers for Disease Controls and Prevention (“CDC”). We also provide workplace drug testing services, testing urine, hair, and oral fluid specimens, and are certified by the U.S. Department of Health and Human Services (“HHS”) to perform drug testing using electronic custody and control forms for federally-mandated, safety-sensitive workers.

We offer a wide range of employer population health services, including biometric screenings, flu shots and related preventative services that leverage clinical data to improve population health outcomes and reduce healthcare spend. Our solutions enable employers to leverage screening insights to identify chronic disease risks, guide employees to needed in-network care, and improve employee health with intervention services. Our offerings emphasize the importance of identifying and reducing health risks, including (i) a program designed to prevent diabetes and other chronic conditions, (ii) early screenings for treatable cancers, such as prostate and colorectal, and (iii) engaging with partner-provided health coaching programs to help individuals adopt healthier behaviors to improve health outcomes. These services are sold directly to employers, through resellers and health plan partners.

We offer health IT solutions, including our products and national healthcare provider network, to help healthcare organizations and clinicians empower better health by leveraging the power of our significant information assets, including one of the world's largest databases of de-identifiable clinical lab results, and our technology prowess, including our history of providing leading IT for diagnostic information services. Our portfolio of offerings is designed to address analytic, clinical and financial needs. The solutions help healthcare organizations and clinicians analyze and put in context data, and enable them to connect across the healthcare system and engage with their stakeholders. They can enter, share and access clinical information without costly IT implementation or significant workflow disruption.

We offer population health solutions to clinicians, health plans, and hospitals. Our services build on the power of our information assets and data capabilities and help our customers deliver better care to their patient populations by identifying gaps in care in a population, providing clinical solutions to close the gaps and fostering consumer engagement with a solution. To help support hospitals in the operation of their own labs, our key Collaborative Lab Solutions offerings include lab management outsourcing, test menu optimization and spend consolidation, supply chain management, and providing advanced data solutions. For clinicians, Quest® Lab StewardshipTM employs machine learning to help optimize medically-appropriate laboratory test utilization. Our extended care services (e.g., home collection kits for lab testing) help deliver better care to patient populations by identifying and filling gaps in care for patient populations and by enabling delivery of the most effective healthcare to the right populations and individuals. These services leverage the power of our assets (e.g., our extensive clinical data and data analytics services) and capabilities (e.g., call centers, patient service centers, mobile phlebotomists) and focus on extending the reach of clinician offices beyond their traditional four walls to assess the health of their populations, and doing so when it is convenient for consumers. Once gaps are identified, we engage patients in our retail sites, in home or by telephone, including through our call centers and our mobile phlebotomists.

We offer services to pharmaceutical companies, including clinical trials laboratory testing, population analytics and patient engagement services. We also develop in vitro diagnostic tests for FDA submissions as companion diagnostics, laboratory developed testing services (“LDTs”) for complementary diagnostics, and offer an array of assets and services to support the development of diagnostic insights, including our robust data set and patient services network. In addition, we offer Quest Clinical Trials Connect™ to help accelerate clinical trials (and thus the speed of drugs to market) through better patient recruitment, involvement and management, and improved physician outreach.

In 2024, we acquired LifeLabs, a company that provides laboratory diagnostic information and digital health connectivity systems in Canada. During the full year of 2025, LifeLabs performed approximately 23 million test requisitions to help diagnose, treat, monitor and prevent diseases for millions of Canadians. LifeLabs operates approximately 15 laboratories, over 350 collection centers in British Columbia, Ontario and Saskatchewan, and an extensive network of couriers and mobile phlebotomists. LifeLabs also partners with governments and companies to develop technologies and customized services.

Diagnostic Solutions

Our risk assessment service, ExamOne®, is the largest provider of risk assessment services to the life insurance industry in North America and comprises underwriting support services, including data gathering, paramedical examinations and clinical laboratory testing and analytics, designed to assist life insurance companies objectively to evaluate the mortality

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risks of applicants. Most specimen collections and paramedical examinations are performed by our network of paramedical examiners at the applicant's home or workplace, but they also are offered at hundreds of our patient service centers and many additional locations. ExamOne® also offers other national specimen collection and health data solutions that provide fast and accurate insights for clinical research and diagnostics programs, as well as academic studies.

We also offer our award-winning Quanum® Enterprise Content Solutions™ for hospitals, to connect data to decision-making and help clinicians advance clinical and operational strategies. Healthcare organizations use Quanum® Enterprise Content Solutions™ at approximately 1,400 sites in North America.

THE CLINICAL TESTING INDUSTRY

Key Trends

The healthcare system in the United States continues to evolve and industry change is likely to be extensive. Because diagnostic information services is an essential healthcare service, we believe that the industry will continue to grow over the long term. There are a number of key trends that we expect will continue to have a significant impact on the growth and the nature of the diagnostic information services business in the United States and on our business. These trends, discussed in the table below, present both opportunities and risks. We believe that several of the trends, including consolidation, price transparency and consumerization, are favorable to our business.

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We believe that these changing market fundamentals will benefit lower-cost, high-value providers like Quest, and that we are well positioned to grow from the changing market conditions and benefit from the long-term growth expected in the industry.

Customer Channels

We provide diagnostic information services to a broad range of customers within our primary customer channels of physicians, hospitals, and patients and consumers. While in many cases, the individual that orders our services is not responsible for paying for these services, consumers are more frequently requesting and paying for tests themselves. Increasingly, patients are bearing greater responsibility for some portion of the payment for the services we provide to them, even if a third party is primarily responsible for payment. In the table below, we provide a summary of our different customer channels. For more information on our growth strategy supporting these customer channels, see above under the heading “Our Strategy."

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Health Plans, Government Agencies and Other Payers

Most of the services we perform are paid for by third-party payers, including large national health plans, managed care organizations and other health insurance providers, regional and local health plans and government payers, which includes Medicare and Medicaid. These customers typically reimburse us as a contracted (or out-of-network) provider for services rendered to their members. In certain locations, health plans may delegate to Independent Physician Associations (“IPAs”) or other alternative delivery systems (e.g., physician organizations, ACOs, patient-centered medical homes) the ability to negotiate for diagnostic information services on behalf of certain members. Increasingly, these customers are interested in value-based arrangements. Health plans and IPAs often require that diagnostic information services providers accept discounted fee structures or assume all or a portion of the financial risk associated with providing such services through capitated payment arrangements. Under capitated payment arrangements, we provide services at a predetermined monthly reimbursement rate for each covered member, generally regardless of the number or cost of services provided by us. Under some capitated programs, we may provide certain services on a negotiated fee-for-service basis. Reimbursement under programs that do not provide for capitated payments is typically negotiated on a fee-for-service basis. Reimbursement from our five largest health plans totaled approximately 20%, and no one health plan accounted for 10%, of our consolidated net revenues in 2025. Health plans typically negotiate directly or indirectly with a number of diagnostic information services providers, and represent nearly one-half of our total clinical testing volume and approximately 40% of our net revenues from diagnostic information services.

There has been a trend of consolidation among health plans. Some health plans also have narrowed their provider networks. In addition, some health plans have established "preferred provider" networks within their broader networks (e.g., UnitedHealthcare's Preferred Lab Network), in effect distinguishing among contracted providers. We are also sometimes a member of a “complementary network.” A complementary network generally is a set of contractual arrangements that a third party maintains with various providers that provide discounted fees for the benefit of its customers. A member of a health plan may choose to access a provider not contracted directly by their health plan but contracted with a complementary network. In such instance, the provider will be reimbursed at a rate negotiated by the complementary network. We offer to health plans services and programs that leverage our Company's expertise and resources, including our superior patient access, comprehensive test menu, medical staff, data, IT solutions, and wellness and population health management capabilities. Our Company has access to a very high percentage of the insured lives in the United States, including very strong access in key high-population states. We believe that this strong access increases our attractiveness to other customer channels, including physicians, patients and employers.

We also provide services on a fee-for-service basis to federal, state and local governmental agencies. Historically, most Medicare and Medicaid beneficiaries were covered under the traditional Medicare and Medicaid programs administered by the federal government. Over the last several years, the federal government has expanded its contracts with private health insurance plans for Medicare beneficiaries and has encouraged such beneficiaries to switch from the traditional programs to the private programs, called “Medicare Advantage” programs. There has been growth of health insurance providers offering Medicare Advantage programs and of beneficiary enrollment in these programs. States also have mandated that Medicaid beneficiaries enroll in private managed care arrangements. We also provide additional services to and in conjunction with government agencies across the United States, including arrangements to support the preparedness for certain viruses by ensuring a national commercial laboratory provider is able to quickly supplement public health laboratories in the event there is an infectious disease outbreak in people.

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Competition

While there has been consolidation in the diagnostic information services industry in recent years, which we expect to continue, our industry remains fragmented and highly competitive. We primarily compete with three types of clinical testing providers: other commercial clinical laboratories, including smaller regional and local commercial clinical laboratories and specialized advanced laboratories; hospital-affiliated laboratories; and physician-office laboratories. Our largest commercial clinical laboratory competitor is Laboratory Corporation of America Holdings, Inc. We also compete with other providers, including large physician group practices and providers of consumer-initiated testing. In anatomic pathology, we compete with anatomic pathology practices, including those in academic institutions and large physician group practices, and providers of emerging digital pathology solutions. Some physician practices establish their own histology laboratory capabilities and/or bring pathologists into their practices, thereby reducing referrals from these practices and increasing the competitive position of these practices.

Hospitals generally maintain on-site laboratories to perform testing on their patients (inpatient or outpatient). In addition, many hospitals compete with commercial clinical laboratories for outreach (non-hospital patients) testing. Hospitals may seek to leverage their relationships with community clinicians and encourage the clinicians to send their outreach testing to the hospital's laboratory. As a result of this affiliation between hospitals and community clinicians, we compete against hospital-affiliated laboratories primarily based on quality and scope of service as well as pricing. In addition, hospitals may have more, or more convenient, locations in a market. Hospitals that own physician practices may encourage or require the practices to refer testing to the hospital's laboratory. There has been a trend of hospitals acquiring physician practices, increasing the percentage of physician practices owned by hospitals. Increased hospital ownership of physician practices may enhance clinician ties to hospital-affiliated laboratories and may strengthen their competitive position. The formation of ACOs and their approach to contracts with healthcare providers also may increase competition to provide diagnostic information services. In addition, new players have recently started to provide clinical lab testing services (e.g., employers; government agencies) and market activity may continue to increase the competitive environment.

We believe that providing the most attractive service offering in the industry, including a comprehensive test menu, innovative test offerings, a positive customer experience, deep medical and scientific expertise, high quality, leading access and distribution, and data-powered integrated IT solutions provide us with a competitive advantage. We believe that as a large diagnostic information services provider we can serve our customers more effectively due to our larger network and lower cost structure. In addition, market activity may increase the competitive environment.

The diagnostic information services industry is faced with changing technology, new product introductions and new service offerings. Competitors may compete using advanced technology, including technology that enables more convenient or cost-effective testing. Digital pathology, still in an emerging state, is an example of this. Competitors, including other diagnostic services and healthcare technology companies, also may compete with us using new testing service offerings that can be performed outside of a commercial clinical laboratory, including point-of-care testing that can be administered by physicians in their offices, complex testing that can be performed by hospitals in their own laboratories, and home testing that can be carried out without requiring the services of providers like us.

The risk assessment and healthcare IT industries are highly competitive. We have many competitors, some of which have much more extensive experience in these industries and some of which have greater resources. We compete in the risk assessment business by seeking to provide a wider array of quality, integrated services than our competitors, faster services completion and a superior applicant experience. We compete in the healthcare IT industry by offering solutions that foster better patient care and improve performance for healthcare providers, particularly smaller and medium sized physician practices.

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GENERAL

Human Capital Management. In 2023 we introduced The Quest Way, which has three core components: Our Purpose: why we exist; our Strategy: how we grow; and our Culture: how we work. Our focus on delivering across The Quest Way drives our approach to human capital management. Effectively managing our human capital resources is a priority with key components that include culture, safety and well-being programs, and employee engagement, and attracting, training, development and succession planning. Our Board of Directors oversees our human capital management, including by receiving management reports on key areas, strategies, and initiatives. Additional information about our human capital management strategies and initiatives is available in our annual corporate responsibility report.

As of December 31, 2025, we have nearly 57,000 employees globally (including LifeLabs’ approximately 6,800), of whom approximately 46,000 are full-time and the remainder are part-time or on-call. Approximately 70% of our employees globally are women (including approximately 75% at LifeLabs). A majority of our employees work directly with our customers or in our laboratories. Fewer than 1% of our U.S. employees are represented by a union. We believe that our overall relations with our employees are good.

Culture. We foster a strong culture, built on our Code of Ethics, which reinforces our commitment to integrity and aligns with our Purpose and brand. In 2023, we introduced The Quest Way and the 5Cs of Culture —Customer First, Care, Curiosity, Collaboration and Continuous Improvement—to define the behaviors we value and aspire to, every day. The 5Cs are integrated into our daily management practices, including recognition, training and performance reviews, to encourage all employees to embody the 5Cs in their daily activities.

We understand the need to create an environment where employees can bring their whole selves to work, and our philosophy embodies our commitment to promote inclusion by consistently inviting new perspectives and exploring new experiences. We aim to harness the unique mix of capabilities, talents, cultures, beliefs and experience of our employees and create a workforce that feels comfortable sharing these perspectives. We focus on Culture, Talent and Community across the entire talent lifecycle and prioritize supporting all employees throughout their careers at Quest. We continue to prioritize our leadership training programs supporting early careerists, mid-career managers and senior executives. Additionally, we launched a council comprised of leaders from our Employee Business Networks to offer regular feedback to organizational leaders on opportunities to further enhance our culture.

Our Quest Management System, supports our effort to maintain a focus on high performance. We also focus on building and maintaining a collaborative and inclusive culture in which all employees are empowered to raise and discuss difficult issues and are valued for their strengths, experience and unique perspectives. We encourage our employees to actively participate in their communities, and support their participation, through our Employee Business Networks and Matching Gift Program. All Employee Business Networks are open to all employees to participate in. Our Everyday Excellence program elevates our focus on the 5C of Customer First through guiding principles for our entire organization to support a superior customer experience and inspire employees to be their best every day, with every person and with every customer interaction; the program is integrated into frontline employee behavioral standards. Our Recognition Quest Program reinforces our commitment to recognize above and beyond contributions and to demonstrating how much we value, care for and appreciate one another by regularly celebrating and rewarding one another as we work together.

Safety and Well-Being. The health and safety of our employees is of paramount concern. We use a systematic, risk-based approach to develop tailored incident prevention and response programs designed to keep our employees safe in each of our different functional areas and use data insights and a detailed audit program to foster the effectiveness of our programs. We have a comprehensive curriculum of annual safety training, as well as training for new employees. As part of our comprehensive and competitive compensation and benefits program, we also offer innovative initiatives to support the well-being of our employees and their families through our HealthyQuest™ program. The cornerstone of HealthyQuest™ is our Blueprint for Wellness® program, which empowers our employees and their spouses and partners with health insights based on lab and biometric data and invites them each year to take the initiative to improve their physical and mental health. We also offer comprehensive medical and mental health plans. HealthyQuest™ focuses on prevention, progression and reversal, through which we offer a HealthyQuest™ Employee Business Network and intervention programs designed to engage employees in managing their health, including access to medical expertise and support programs tailored to their individual needs, helping them to adopt healthier behaviors and access better care at lower costs. These programs include customized programs for conditions such as type 2 diabetes management, chronic kidney disease, cardiovascular disease, specialty drugs,

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weight management, zero-cost lab testing, and special support for orthopedic surgery and for cancer and other serious diagnoses.

Engagement. Actively listening to our employees is fundamental to Quest’s culture. We have always sought to foster the engagement of our employees and take action to improve the employee experience, through the use of regular employee insight surveys. Employee engagement has been a metric in the annual incentive plan for our executive officers since 2013. Since 2020, our strategy for gathering employee feedback utilizes more frequent employee insight surveys. This approach is designed to build an agile culture, based on continuous feedback that fuels ongoing conversations about priorities, performance, opportunities and growth, to result in a higher performing organization and committed employees. This is complemented by lifecycle surveys for new hire and departing staff. In addition, we conduct surveys of our employees regarding important topics and hold regular monthly meetings among hundreds of company leaders to foster increased communication across the company regarding topics of concern to employees.

Attracting, Training, Development and Succession Planning. We have a strong program designed to attract a qualified work force that will enable us to achieve our business goals. For example, we are partnering with universities and specialized healthcare schools to help build our pipeline of expertise in medical technology, cytology and histology, and we have teamed up with a third-party phlebotomy training program to train and certify phlebotomist candidates who can join our ranks upon graduation. We provide training on a wide array of topics to our employees through live and online formats, including opportunities that can be accessed through their mobile devices. We also offer a number of development opportunities for our employees through a robust library of offerings in our Learning Management System, EMPower. We also offer mentoring and education programs, including a higher education tuition assistance program, My Quest for Education. Among participants in the My Quest for Education program, 54% have received promotions and 36% have made lateral career moves. We continue to invest in INSPIRE, a frontline development program focused on enhancing service excellence for our customer-facing employees. In addition, we provide leadership training opportunities for employees at all levels, including a manager essentials curriculum, our Leading Quest Supervisor and Manager Core program, our director-level Leading Quest for Business Impact program, Financial Acumen for Business Leaders, leadership coaching programs and trainings to strengthen critical leadership skills. We also deliver a number of programs tailored to specific functions to drive a high-performance culture and sharpen the capabilities needed to lead our organization (e.g., programs focused on Commercial, Finance, Pathology, R&D, and Product Development). Quest’s robust talent review and succession planning process assesses current and future organizational needs in combination with the capabilities and aspirations of our employees to ensure we have the right talent, in the right roles, at the right time. For leaders, we have robust succession plans and leverage several inputs, inclusive of formal assessments, to inform customized development plans.

Sales and Marketing. Our Diagnostic Information Services business has a unified commercial organization focused on the sale of most of our services. It coordinates closely with our clinical franchises (discussed above under the heading "Organized to Drive Growth and Value") and marketing organization. The commercial organization is centrally led, and is organized regionally, in conjunction with our operations organization, to focus on local customer needs and to ensure aligned delivery for our customers. Our commercial organization employs leading processes and tools and strong management discipline. We provide industry-leading training and development, focus on opportunities with hospitals and specialty physicians, and foster a customer-focused, performance-driven culture. We also maintain distinct sales and marketing organizations for our offerings in Diagnostic Solutions and our employer testing services.

Technology. We use information systems extensively in virtually all aspects of our business, including clinical testing, test ordering and reporting, billing, customer service, logistics and management of data. We endeavor to establish systems that create value and efficiencies for our Company and customers. The successful delivery of our services depends, in part, on the continued and uninterrupted performance of our information technology systems. We take precautionary measures to prevent problems that could affect our IT systems.

Some of our historic growth has come through acquisitions and, as a result, we continue to use multiple information systems. We have made significant progress implementing common systems in our regional laboratories, and we continue to standardize laboratory information and billing systems across our operations. In February 2025, we committed to Project Nova, a multi-year project to modernize our "Order to Cash" business processes, including the related information technology infrastructure and underlying enabling technologies. We are partnering with Epic, a third-party licensor, to assist in the implementation of Project Nova. We expect to deliver value throughout the implementation of Project Nova, which we expect will be completed in 2031 to 2032, as it unlocks a variety of streamlined operational benefits, reduced technology-related operating costs, accelerated revenue opportunities and improvements to the customer and patient experience. As each of our standardization projects are completed over the coming years, we expect that they will result in significantly more centralized systems, improved operating efficiency, more positive customer experiences and enhanced control over our operational

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environment. Even after we complete our efforts to standardize our legacy systems, we will need to focus on standardizing systems in connection with future business acquisitions.

Quality Assurance. At Quest, our Quality and Regulatory Affairs strategy is rooted in our Purpose: working together to create a healthier world, one life at a time. Our mission is to ensure the highest standards of quality in every test and insight we deliver – enabling physicians and their patients to make confident, informed decisions about patient health. Guided by our operating principles, the Quality and Regulatory Affairs function drives quality and regulatory compliance across the enterprise as a true business partner in advancing patient-first decision making. We promote a "Speak Up for Quality" culture, where every team member is empowered to raise concerns, ask questions and share ideas that strengthen reliability and patient trust. Recently, we enhanced enterprise engagement through our first enterprise-wide Quality Week, celebrating the work of teams across the Company and reinforcing shared accountability for quality outcomes.

In our laboratory operations our quality assurance efforts focus on pre-analytic, analytic and post-analytic processes, including positive patient identification of specimens, appropriate specimen transport, analysis and report accuracy, reference interval establishment and review, statistical process control and personnel training for our laboratories and patient service centers. As part of our quality assurance program, we utilize internal proficiency testing, comprehensive quality control and rigorous process audits. We utilize comprehensive and digitized data analytics software that implements advanced automated quality control procedures, offering both real-time and post-analytic analysis of data at the laboratory and enterprise level. In 2025, to modernize our quality ecosystem, we deployed new technology solutions, expanded public health reporting capability, and selected an enterprise electronic Quality Management System platform – investments that build on our strong infrastructure and support future scalability. We monitor test results to identify trends, biases, instrument failures and population shifts through digitization and data analytics. We also focus on the licensing, credentialing, training and competence of our professional and technical staff. For example, our cytotechnologists and pathologists participate in an internal peer-review evaluation and one or more external individual proficiency testing programs.

We have accreditation or licenses for our clinical laboratory operations from various regulatory agencies or accrediting organizations, such as CMS, The College of American Pathologists (“CAP”) and certain states. All of our laboratories participate in external quality surveillance programs, including proficiency testing programs administered by CAP and several state agencies. CAP is an independent, nongovernmental organization of board-certified pathologists approved by CMS to inspect clinical laboratories to determine compliance with the standards required by the Clinical Laboratory Improvement Act (“CLIA”). CAP offers an accreditation program to which clinical laboratories may voluntarily subscribe. All of our major laboratories, including our laboratories outside the United States, a number of our rapid response laboratories, and our biorepository facility are accredited by the CAP. Accreditation includes on-site inspections and participation in the CAP (or equivalent) proficiency testing program. In addition, some of our laboratories also have International Organization for Standardization (ISO) certification for their quality management systems. For example, we have achieved ISO 14001 certification for our Cleveland HeartLab and laboratory facilities in Chantilly, VA, Marlborough MA, Lewisville TX and San Juan Capistrano, CA. ISO 14001 is an internationally recognized management system that leverages leadership involvement and employee engagement to help organizations ensure compliance with regulatory standards, improve their environmental performance, provide a competitive advantage and gain the trust of stakeholders, and achieve strategic goals by incorporating environmental issues into business management.

We maintain a robust Supplier Quality Program designed to ensure a high-quality supplier network and to raise the bar of quality expectation across that network. We expect suppliers to provide the highest quality products and services and to embrace an ethic of transparent quality collaboration. In our Supplier Quality Program, we aim to ensure and improve the quality of purchased products and services. Our suppliers are expected to operate under quality management principles that meet industry standards, strive for zero defect manufacturing, use statistical analysis to reduce variation and meet applicable regulatory standards. In choosing suppliers, we evaluate their quality systems and quality performance metrics. Our supplier qualification process is risk-based, with assessments and on-site audits based on risk tiers and supplier quality management system compliance. Contracts with our suppliers include specific quality, compliance, and change management provisions as appropriate. We use supplier quality engineers who are trained to audit on ISO standards and FDA regulations applicable to suppliers’ processes, and a procurement engineering team to assist with qualification and validation of new supplies and products. We actively manage supplier performance, utilizing a problem reporting and resolution process designed to drive to root cause and corrective actions. We maintain a continuous improvement dialogue with our suppliers, and with operationally critical suppliers deliver a supplier scorecard that supports continuous improvement.

In addition, we maintain quality assurance programs for hospital laboratories that we manage, many of which also maintain their own policies and procedures.

Intellectual Property Rights. We own significant intellectual property, including patents, patent applications, technology, trade secrets, know-how, copyrights and trademarks in the United States and other countries. From time to time,

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we also license patents, patent applications, technology, trade secrets, know-how, copyrights or trademarks owned by others; we also may license our intellectual property to others. In the aggregate, our intellectual property assets and licenses are of material importance to our business. We believe, however, that no single intellectual property asset is material to our business as a whole. Our approach is to manage our intellectual property assets, to safeguard them and to maximize their value to our enterprise. We actively defend our important intellectual property assets and pursue protection of our products, processes and other intellectual property where possible.

Enterprise Risk Management Program. We maintain an enterprise risk management program, which is led by our executive leadership and overseen by our Board of Directors, that is designed to promote a culture of risk awareness throughout the Company's key business, operations and support functions. Our program, which is integrated with the Company’s governance, performance management and internal control frameworks, entails a formal continuous process that identifies, assesses, mitigates and manages the risks from both internal and external conditions that could significantly impact the Company and influence its business strategy and performance. The program, which is managed by an enterprise risk management team, is designed based on the most recent framework issued by the Committee of Sponsoring Organizations of the Treadway Commission, and we benchmark it against best practices. We focus on the following risk types:

•Operational risk - risks arising from systems, processes, people and external events that affect the Company’s operational objectives or fundamental reason for its existence, including: product life-cycle and execution; service quality and performance; information management and data protection and security, including cybersecurity; supply chain and business disruption; and other risks, including human capital, reputation and environmental.

•Financial risk - risks arising from the Company’s ability to meet its financial obligations pursuant to its strategic and operational objectives, including exposure to broad market and more specific industry risk that could impact liquidity, interest rate, credit, pricing and reimbursement, and also to internal and external financial reporting.

•Legal and compliance risk - risks arising from the regulatory and enforcement environment, legal proceedings and adherence to ethics and compliance policies and procedures.

•Strategic risk - risks that will impede the Company’s plan to achieve its Purpose and apply its core values, including changes in the broad market and Company's industry, business development and restructuring activities, competitive threats and practices, technology and product innovation, and public policy.

As part of our program, together with our Board of Directors, we routinely assess our enterprise level risks, emerging risks, overall Company-level risk tolerance and the effectiveness of risk management, and monitor the progress of and resources applied to risk mitigation. Our Board of Directors and its committees receive updates and training from internal and external experts on topics that are relevant to overall risk management. Our primary risk factors are discussed in "Risk Factors" below.

Billing; Government Reimbursement. We generally bill for diagnostic information services on a fee-for-service basis under one of two types of fee schedules; fees may be negotiated or discounted. The types of fee schedules are:

•“Client” fees charged to physicians, hospitals and institutions for which services are performed on a wholesale basis and which are billed on a monthly basis.

•“Patient” fees charged to individual patients and certain third-party payers on a claim-by-claim basis.

Billing for diagnostic information services is very complicated. Our customers have different billing requirements. Some billing arrangements require us to bill multiple payers, and there are several other factors that complicate billing (e.g., disparity in coverage and information requirements among payers; incomplete or inaccurate billing information provided by ordering clinicians; and lack of access to patients before testing). We maintain compliance policies and procedures for our billing practices, and we audit our practices for compliance with applicable laws and regulations and internal policies and procedures.

With regard to the clinical testing services performed on behalf of Medicare beneficiaries, we generally must bill Medicare directly and must accept the Medicare carrier's fee schedule amount for covered services as payment in full. In addition, state Medicaid programs are prohibited from paying more (and in most instances, pay significantly less) than Medicare. Currently, Medicare does not require the beneficiary to pay a co-payment for diagnostic testing services reimbursed under the Clinical Laboratory Fee Schedule, but generally does require a patient deductible and co-insurance for anatomic pathology services.

Part B of the Medicare program contains fee schedule payment methodologies for clinical testing services performed for covered patients, including a national ceiling on the amount that carriers could pay under their local Medicare clinical

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testing fee schedules. Historically, the Medicare Clinical Laboratory Fee Schedule and the Medicare Physician Fee Schedule established under that program have been subject to change, including each year. Pursuant to PAMA, reimbursement rates for many clinical laboratory tests provided under Medicare were reduced during 2018 - 2020. Unfortunately, by relying on laboratory reported data alone in 2017, CMS did not receive comprehensive and representative data needed to set Medicare rates that reflected the commercial market, as required under PAMA. Independent laboratories were overrepresented, and hospitals and physician office laboratories were underrepresented, making the first round of PAMA cuts excessive. The first three years of cuts greatly exceeded the original 10-year savings projections. Starting in 2020, Congress has repeatedly acted to delay PAMA implementation by delaying the next round of data reporting (2020-2026) and Medicare cuts (2021-2026). However, the structural flaws of PAMA still need to be addressed to mitigate future excessive cuts. Congress introduced legislation in 2025, the Results Act, which would reform PAMA and create a true market-based CLFS.

REGULATION

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Compliance. We strive to conduct our business in compliance with all applicable laws and regulations. We license and maintain appropriate accreditations for all of our laboratories and, where applicable, patient service centers, as required by federal and state agencies. We have a long-standing and well-established compliance program. The Quality and Compliance Committee of our Board of Directors oversees, and receives periodic management reports regarding, our compliance program. Our program includes detailed policies and procedures and training programs intended to ensure the implementation and observance of all applicable laws and regulations (including regarding billing and reimbursement, and privacy of protected health information and personally identifiable information) and Company policies. Further, we conduct in-depth reviews of procedures and facilities to assure regulatory compliance throughout our operations. We conduct annual training of our employees on these compliance policies and procedures.

As an integral part of our billing compliance program, we investigate reported or suspected failures to comply with Medicare or Medicaid reimbursement requirements. As a result of these efforts, we have periodically identified and reported overpayments, refunded the payers for overpayments and taken appropriate corrective action.

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AVAILABLE INFORMATION

The Securities and Exchange Commission (the “SEC”) maintains an internet site, www.sec.gov, that contains annual, quarterly and current reports, proxy and information statements and other information that issuers file electronically with the SEC. We file reports, proxy statements and other information with the SEC; they are publicly available at the SEC's internet site.

Our internet address is www.QuestDiagnostics.com. The information on or accessible through our website is not part of and is not incorporated by reference into this Report. We make available free of charge, on or through our Investor Relations webpage (www.QuestDiagnostics.com/investor), our proxy statements, Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and any amendments to those reports filed or furnished pursuant to the Securities Exchange Act of 1934, as amended (the “Exchange Act”), as soon as reasonably practical after such material is filed with, or furnished to, the SEC.

We also maintain a Corporate Responsibility webpage that provides information about our corporate responsibility program, including our efforts related to community giving, governance and sustainability and our annual Corporate Responsibility Report.

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INFORMATION ABOUT OUR EXECUTIVE OFFICERS

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