UnitedHealth Group

UnitedHealth Group Incorporated
Type	Public company
Traded as	NYSE: UNH
Industry	Managed health care, health services, pharmacy benefit management
Founded	1977 (as UnitedHealthCare Corporation)
Founder	Richard T. Burke
Headquarters	Eden Prairie, Minnesota, United States
Key people	Stephen Hemsley (Chief Executive Officer)
Employees	Approximately 400,000

UnitedHealth Group Incorporated is an American multinational health care and insurance company based in Eden Prairie, Minnesota. It is the largest health insurer in the United States, covering more than fifty million people, and through its Optum division one of the largest providers of health services, pharmacy benefit management and health data analytics in the world. Measured by revenue it is consistently among the four or five largest companies in the United States and the largest health care company anywhere.

The group sells insurance under the UnitedHealthcare brand and delivers care, pharmacy services and technology under the Optum brand. The combination is the defining feature of the business: UnitedHealth both pays for medical care and, increasingly, supplies it, employing or affiliating with around ninety thousand physicians, which makes it the largest employer of doctors in the United States. Whether this integration reduces cost and improves coordination, as the company argues, or creates conflicts of interest that disadvantage patients and independent providers, as its critics argue, is the central question in almost every controversy surrounding it.

The company's market capitalisation exceeded US$400 billion at the end of 2025. It is a component of the Dow Jones Industrial Average and the S&P 500. Stephen Hemsley, who led the group from 2006 to 2017 and then served as chairman, returned as chief executive in May 2025 following the resignation of Sir Andrew Witty amid rising medical costs, a suspended earnings forecast and a share price decline of close to forty per cent.

History

Origins, 1974 to 1999

The company's origin lies in Charter Med Incorporated, founded in 1974 by a group of physicians and other health professionals in Minnetonka, Minnesota. In 1977 Richard T. Burke formed United HealthCare Corporation as a holding company for Charter Med, with the purpose of managing a newly created health maintenance organisation, Physicians Health Plan of Minnesota. Health maintenance organisations had been given federal encouragement by legislation passed in 1973, which required larger employers to offer such a plan as an alternative to conventional indemnity insurance, and the sector expanded quickly through the following decade.

The company went public in 1984. Growth came through a long series of acquisitions of regional health plans, among them Peak Health Care in 1986, the pharmacy benefit manager Diversified Pharmaceutical Services in 1989, the Arizona insurer MetraHealth in 1995 for about US$1.65 billion, and HealthWise of America in 1996. William W. McGuire, a physician who had joined in 1988, became chief executive in 1991 and led the company through this consolidation phase. In 1998 the group was reorganised into a holding structure and renamed UnitedHealth Group, with distinct operating businesses beneath it, and the Ingenix data and analytics unit was established.

Consolidation and the options scandal, 2000 to 2009

The decade after 2000 brought both the group's most aggressive expansion and its first major governance failure. Acquisitions included Oxford Health Plans in 2004 for about US$4.9 billion, Mid Atlantic Medical Services in the same year, PacifiCare Health Systems in 2005 for roughly US$8.1 billion, and John Deere Health Care in 2006. Each transaction extended the geographic reach of the insurance business and increased the group's bargaining power with hospitals and physicians.

In 2006 an investigation established that stock options granted to executives had been backdated to dates on which the share price was at a low, inflating their value. McGuire stepped down as chairman and director, forfeited a substantial part of his holdings and later settled with the Securities and Exchange Commission for about US$468 million, at the time one of the largest settlements ever reached with an individual executive. Stephen Hemsley, then president and chief operating officer, succeeded him as chief executive.

A second matter concerned Ingenix, which maintained a database used across the industry to determine the customary charge for out-of-network medical services. An investigation by the New York attorney general concluded in 2009 that the database systematically understated prevailing charges, causing insurers to underpay reimbursements and patients to bear more of the cost than their policies implied. UnitedHealth paid US$350 million to settle related class litigation and US$50 million towards an independent replacement database, and the arrangement was dismantled.

The Optum era, 2010 to 2020

In 2011 the group consolidated its health services businesses under a single brand, Optum, comprising OptumHealth for care delivery, OptumInsight for data and technology, and OptumRx for pharmacy benefit management. The rebranding was more than cosmetic. It marked a strategic decision to grow the services side of the business faster than the insurance side, on the reasoning that insurance margins were capped by regulation while services were not.

The Affordable Care Act, enacted in 2010, imposed a medical loss ratio requirement obliging insurers to spend a minimum proportion of premium income, eighty or eighty-five per cent depending on the market, on medical care rather than administration and profit. One consequence, not necessarily intended, was to make vertical integration attractive: payments made to a subsidiary that provides care count as medical spending, so an insurer that owns providers can satisfy the ratio while retaining the margin within the group. The expansion of Optum through the following decade is difficult to understand without this.

Optum grew by acquiring physician groups, surgery centres, urgent care chains and technology businesses at a pace of dozens of transactions a year. Notable purchases included the pharmacy benefit manager Catamaran in 2015 for about US$12.8 billion, the physician group DaVita Medical Group in 2019 for about US$4.3 billion, and the home health business LHC Group, agreed in March 2022 for US$5.4 billion. By the mid-2020s Optum generated roughly half of group revenue and a larger share of operating profit than the insurance business from which it had grown.

Andrew Witty, formerly chief executive of GlaxoSmithKline, joined as chief executive of Optum in 2018 and became president of the group in November 2019.

Change Healthcare and the cyberattack, 2021 to 2024

In January 2021 UnitedHealth announced the acquisition of Change Healthcare, the largest health payments and claims clearing platform in the United States, for about US$13 billion. The Department of Justice sued to block the transaction in February 2022 on the grounds that combining the country's largest insurer with the infrastructure through which competing insurers' claims passed would give UnitedHealth access to rivals' commercially sensitive data. A federal court declined to block the deal and it closed in October 2022.

In February 2024 the acquired business was disabled by a ransomware attack attributed to the group ALPHV, also known as BlackCat. Because Change Healthcare processed a very large share of all medical claims in the United States, the outage prevented physicians, hospitals and pharmacies from submitting claims or verifying coverage for weeks. Many small practices could not meet payroll; UnitedHealth advanced billions of dollars in emergency loans to providers. The company acknowledged paying a ransom, and testimony to Congress established that the compromised system had not been protected by multi-factor authentication. Protected health information belonging to an estimated one hundred million people was affected, making it the largest health data breach in American history. The Department of Justice opened a fresh antitrust and Medicare overcharging inquiry in the same month.

Also in 2023 the group announced that it would move its headquarters from Minnetonka to Eden Prairie, Minnesota, and in February 2024 it completed the sale of its Brazilian operations, ending an unprofitable international expansion begun with the purchase of Amil in 2012.

The killing of Brian Thompson

On 4 December 2024 Brian Thompson, chief executive of the UnitedHealthcare insurance subsidiary, was shot and killed outside the New York Hilton Midtown in New York City, where the group was holding an investor event. Luigi Mangione was arrested in Pennsylvania several days later and charged with the murder.

The public reaction was without modern precedent for the killing of a corporate executive. Social media responses were dominated not by sympathy but by expressions of anger at UnitedHealthcare specifically and at American health insurance generally, with widely circulated accounts of denied claims and of treatment delayed or refused. Commentators across the political spectrum described the reaction as disturbing, and it prompted a broad reassessment within the industry of how claim denials were communicated and of the personal security of executives. Several insurers removed leadership biographies from their websites. The episode did not change insurance regulation, but it made the depth of public hostility towards the sector impossible for the industry to treat as marginal.

Recent developments, 2025 to 2026

In May 2025 UnitedHealth announced the resignation of Andrew Witty for personal reasons and the suspension of its annual earnings guidance, citing medical costs in its Medicare Advantage business that had risen far faster than assumed. The shares fell by close to forty per cent over the year to their lowest level in several years. Stephen Hemsley, then chairman, returned as chief executive.

In July 2025 the Wall Street Journal reported that Department of Justice officials were interviewing former employees in connection with the criminal investigation into Medicare Advantage billing. In November 2025 Scott Gottlieb, a former commissioner of the Food and Drug Administration, joined the board. In June 2026 the group announced plans to invest US$3 billion in artificial intelligence during 2026 and 2027, principally in claims processing, clinical documentation and care management.

Organisational structure

UnitedHealthcare

UnitedHealthcare is the insurance arm and operates through four principal lines.

Employer and Individual provides coverage to employers of all sizes and to individuals, both as an insurer bearing the risk and as an administrator of plans in which the employer bears the risk itself, an arrangement covering the majority of large American employers.

Medicare and Retirement serves people aged sixty-five and over, principally through Medicare Advantage, in which the federal government pays a private insurer a fixed amount per enrollee to provide Medicare benefits. UnitedHealthcare is the largest Medicare Advantage insurer in the country, with roughly a quarter of national enrolment, and its long-standing partnership with AARP gives it a distinctive distribution advantage. Medicare Advantage is the most profitable and most politically contested part of the business.

Community and State contracts with state governments to administer Medicaid benefits for low-income residents, a business that expanded substantially after the Affordable Care Act broadened Medicaid eligibility.

Global covers international operations, considerably reduced since the sale of the Brazilian business in 2024.

Optum

Optum Health delivers care directly. Through employed physicians, affiliated practices, surgery centres, urgent care clinics and home-based care, it serves tens of millions of patients, and its acquisitions have made UnitedHealth the largest employer of physicians in the United States. Much of its growth has been in value-based arrangements in which a provider group accepts a fixed payment for a patient's total care and retains any savings.

Optum Rx is a pharmacy benefit manager, one of three that together administer the great majority of American prescription drug benefits. Pharmacy benefit managers negotiate rebates from manufacturers, determine which drugs appear on a plan's formulary and set the terms on which pharmacies are reimbursed. The model has attracted sustained scrutiny from Congress and the Federal Trade Commission over whether rebate structures raise list prices and whether vertically integrated managers steer prescriptions to affiliated pharmacies.

Optum Insight supplies data analytics, revenue cycle management and technology services to hospitals, health systems, insurers and governments, and includes the Change Healthcare business.

Criticism and controversies

The volume of litigation and regulatory action involving UnitedHealth is unusual even by the standards of American health care.

Medicare Advantage billing

Medicare Advantage pays insurers more for patients with more serious diagnoses, a mechanism called risk adjustment intended to prevent insurers from avoiding sick patients. Successive federal investigations, whistleblower suits and inspector general audits have alleged that UnitedHealth systematically recorded diagnoses that made patients appear sicker than they were, through in-home assessments and chart reviews that generated additional diagnoses without corresponding treatment. A Department of Justice civil suit has proceeded for years, and reporting in 2025 established that a parallel criminal investigation was under way. In May 2026 the state of Massachusetts sued the company for defrauding MassHealth, its Medicaid programme, of US$100 million by making older patients appear more seriously ill than they were.

Claim denials and automated decision-making

In 2023 reporting alleged that Optum used an algorithmic model known as nH Predict to determine how long patients recovering in skilled nursing facilities required care, and that the model's estimates were used to terminate coverage despite treating physicians' contrary judgement. A class action followed, alleging that the model's error rate was known internally and that staff were disciplined for deviating from its recommendations. A separate investigation by The Guardian in May 2025 described payments to nursing homes conditional on reducing hospital transfers of residents, an arrangement the company denied was intended to deny necessary care.

Earlier litigation concerned mental health. In Wit v. United Behavioral Health, a federal court found in 2019 that the company's internal coverage guidelines for mental health and substance use treatment were more restrictive than generally accepted clinical standards and had been written with cost in mind, a ruling subsequently narrowed on appeal but widely cited in the debate over parity between mental and physical health coverage.

Other matters

Other actions have included a settlement with the American Chiropractic Association over reimbursement practices; fines imposed by California regulators following the PacifiCare acquisition for mishandling claims; a penalty from the Centers for Medicare and Medicaid Services over administration of a Medicare Part D drug plan; a 2018 New Jersey fine; disputes with the physician staffing company TeamHealth over out-of-network payment; and a shareholder suit filed in May 2024 alleging that Hemsley and Thompson had sold shares while in possession of undisclosed information about the Department of Justice investigation.

In July 2025 a New York Times investigation reported that the company, working with the law firm Clare Locke, had sent legal threats to journalists, social media users and health care commentators over criticism of its practices, a campaign that drew criticism from press freedom organisations.

Context: health insurance in the United States

UnitedHealth's business cannot be understood without the structure of the market it operates in, which differs from that of every other wealthy country.

The United States has no single national health system. Coverage is assembled from several distinct arrangements. Roughly half the population is insured through an employer, an arrangement that dates from wage controls during the Second World War, when employers competed for workers by offering benefits that were not counted as wages and were not taxed. People aged sixty-five and over are covered by Medicare, a federal programme created in 1965. Low-income people are covered by Medicaid, created at the same time and administered jointly by the federal government and the states. Individuals without access to any of these may buy coverage on exchanges created by the Affordable Care Act of 2010, with subsidies varying by income. A residual population, smaller than before 2010 but still numbering in the tens of millions, remains uninsured.

Private insurers participate in almost all of these. They sell and administer employer plans; they run Medicare Advantage, the privatised version of Medicare that now covers more than half of all Medicare beneficiaries; they administer most state Medicaid programmes under contract; and they sell exchange policies. UnitedHealth participates in every one of them, which is the principal reason for its size.

How Medicare Advantage works

Medicare Advantage is the most important single business line in the company and the one that carries the most risk. Under it, the federal government pays a private insurer a fixed monthly amount for each enrollee, adjusted for that person's expected health costs, and the insurer assumes responsibility for providing all Medicare-covered benefits. Insurers typically add extras such as dental, vision and gym membership, funded from the savings they expect to achieve by managing care more tightly than traditional Medicare, which pays any licensed provider for any covered service.

Two features of the design create persistent tension. First, the payment is adjusted by a risk score derived from recorded diagnoses, so an insurer that documents more conditions receives more money. The intent is to prevent insurers from avoiding sick patients; the effect, according to repeated findings by the Medicare Payment Advisory Commission and the Department of Health and Human Services inspector general, is that Medicare Advantage enrollees are coded as sicker than comparable patients in traditional Medicare, at a cost to the programme estimated in the tens of billions of dollars annually. Almost every large Medicare Advantage insurer has faced litigation on this point, and UnitedHealth, as the largest, has faced the most.

Second, because the insurer keeps what it does not spend, there is a direct financial interest in limiting utilisation. Prior authorisation requirements, network restrictions and coverage terminations for post-acute care are the mechanisms through which this operates, and they are the source of most patient complaints about the programme. Congressional hearings in 2023 and 2024 examined denial rates across the largest insurers, and several companies subsequently agreed to reduce the number of services requiring prior approval.

Pharmacy benefit management

Optum Rx belongs to a category of intermediary that exists in no other health system. A pharmacy benefit manager sits between drug manufacturers, insurers and pharmacies. It decides which medicines a plan will cover and on what terms, negotiates rebates from manufacturers in exchange for favourable placement, and sets the amount pharmacies are reimbursed for dispensing.

Three managers, Optum Rx, CVS Caremark and Express Scripts, together administer the great majority of American prescription benefits, and each is owned by a company that also sells insurance or operates pharmacies. Critics, including the Federal Trade Commission in a series of reports from 2024, argue that rebates give manufacturers an incentive to set high list prices from which large discounts can be offered, that patients whose cost sharing is calculated on the list price therefore pay more, that independent pharmacies are reimbursed below cost while affiliated pharmacies are not, and that the flow of money is deliberately opaque. The industry replies that it is the only counterweight to manufacturer pricing power and that it saves plan sponsors a great deal of money. Legislative proposals to separate ownership of pharmacy benefit managers from insurers have been introduced repeatedly and have not passed.

The Change Healthcare attack in detail

The February 2024 attack deserves separate treatment because of what it revealed about concentration in health care infrastructure.

Change Healthcare was not a consumer-facing business and few patients had heard of it. It operated the electronic plumbing through which a large proportion of American medical claims travelled: eligibility checks confirming that a patient was covered, claim submissions from providers to insurers, remittance advice returning from insurers to providers, and electronic prescribing. Estimates of the share of claims passing through it ranged from a third to nearly half.

When the systems were taken offline on 21 February, the consequence was immediate and national. Pharmacies could not confirm whether a prescription was covered. Hospitals could not submit claims and therefore received no payments. Small physician practices, which typically hold only a few weeks of operating cash, began missing payroll within a month. Some closed. The American Hospital Association described it as the most significant cyberattack on the health care system in United States history.

UnitedHealth advanced more than US$6 billion in interest-free loans to affected providers, restored systems in stages over several months and acknowledged paying a ransom of a reported US$22 million, which was followed by a dispute among the attackers and a second extortion demand. Testimony before Congress in May 2024 established that the compromised remote access server had not been protected by multi-factor authentication, a control that is standard practice and was in the process of being applied across acquired systems when the attack occurred.

The breach notification, completed through 2024 and 2025, put the number of people whose protected health information was affected at approximately one hundred million, the largest such breach ever recorded in the United States. The episode strengthened the argument that the vertical integration which had made UnitedHealth efficient had also created a single point of failure with no substitute, and it featured prominently in subsequent antitrust scrutiny of the group.

Leadership

Richard T. Burke founded United HealthCare Corporation in 1977 and led it until 1988. He later owned the Phoenix Coyotes ice hockey team and remained on the board for many years.
William W. McGuire (1991 to 2006), a pulmonologist by training, built the company through the acquisition programme of the 1990s and early 2000s. His departure in the options backdating scandal produced one of the largest personal settlements in the history of American securities enforcement.
Stephen Hemsley (2006 to 2017) restored the company's standing after the scandal, oversaw the creation of Optum and presided over the period in which revenue quadrupled. He served as chairman thereafter and returned as chief executive in May 2025.
David Wichmann (2017 to 2021) continued the Optum expansion and led the company through the first year of the pandemic.
Sir Andrew Witty (2021 to 2025), previously chief executive of GlaxoSmithKline and knighted for services to the economy and to the United Kingdom's life sciences sector, led the group through the Change Healthcare acquisition and its aftermath and resigned as medical costs rose beyond forecast.

Brian Thompson led the UnitedHealthcare insurance subsidiary from 2021 until his death in December 2024. He had joined the company in 2004 from PricewaterhouseCoopers and had previously run the Medicare and Retirement business.

Competition

UnitedHealth competes with a small number of similarly integrated organisations, each of which has followed a comparable strategy of combining insurance with services.

CVS Health owns the insurer Aetna, the pharmacy benefit manager Caremark, a national pharmacy chain and the primary care group Oak Street Health. Cigna owns Express Scripts and the health services business Evernorth, and sold its Medicare business in 2025 to concentrate on employer coverage and pharmacy services. Elevance Health, formerly Anthem, holds Blue Cross Blue Shield licences in fourteen states and has built the Carelon services division on a similar model. Humana concentrates almost entirely on Medicare Advantage and owns the primary care chain CenterWell. Centene specialises in Medicaid and exchange coverage.

Below these are the non-profit Blue Cross Blue Shield plans, regional insurers and integrated systems such as Kaiser Permanente, which combines insurance, hospitals and an employed physician group within a single non-profit structure and is frequently cited as the model that vertical integration in the for-profit sector imitates without replicating.

Competition in this market is unusual because the buyers are largely institutional. An employer or a state government chooses a plan for a population, and the individuals covered often have no choice at all. In Medicare Advantage, where individuals do choose annually, competition is intense during the autumn enrolment period and is conducted largely through advertising and supplementary benefits rather than price, since the premium is frequently zero.

Terminology

Medical loss ratio is the share of premium income spent on medical care. Federal law requires it to be at least eighty per cent in individual and small group markets and eighty-five per cent in large group markets, with rebates owed to customers if it falls short.

Risk adjustment is the mechanism by which payments to an insurer are increased for enrollees with more serious recorded diagnoses.

Prior authorisation is the requirement that a provider obtain an insurer's approval before delivering a service, used to control utilisation and the most common source of complaint from physicians.

Value-based care describes payment arrangements in which a provider receives a fixed sum for a patient's overall care rather than a fee for each service, and shares in savings or losses against that sum.

Formulary is the list of drugs a plan covers, together with the tier determining what the patient pays.

Self-funded plan is an arrangement in which an employer bears the cost of claims itself and pays an insurer only to administer the plan. Most large American employers operate this way, which means a substantial part of UnitedHealthcare's membership represents administrative services rather than insurance risk.

Finance

UnitedHealth's revenue passed US$100 billion in 2012, US$200 billion in 2019 and US$400 billion in 2024, growth driven roughly equally by enrolment in government-funded programmes and by the expansion of Optum. Because the insurance business collects premiums before paying claims, the group holds large investment balances, and because Optum's revenue includes payments from UnitedHealthcare, consolidated figures eliminate a substantial volume of internal transactions.

The most closely watched figure is the medical care ratio, the proportion of premium revenue paid out in medical costs. A change of a single percentage point moves billions of dollars of profit, which is why the deterioration in this ratio during 2024 and 2025, driven by higher use of medical services among Medicare Advantage members after the pandemic, was sufficient to remove tens of billions of dollars of market value and to precipitate a change of chief executive.

Lobbying and political activity

UnitedHealth is among the largest spenders on lobbying in the United States health sector and a significant contributor through its political action committee. Its policy interests centre on the payment rates and risk adjustment rules of Medicare Advantage, on the regulation of pharmacy benefit managers, and on proposals for a public insurance option or single-payer system, which the industry has consistently opposed.

The Lewin Group, a health policy consultancy acquired with Ingenix in 2007, produced analyses widely cited in legislative debate. Critics objected that its findings were reported as independent research while its owner had a direct financial interest in the outcomes, and the firm's disclosure practices were changed in response. It was divested in 2022.

Assessment

UnitedHealth is the clearest expression of how American health care actually works, which is why arguments about it are rarely only about the company. It grew by being better than its competitors at the things the system rewards: negotiating with providers, managing risk pools, capturing government programme enrolment and, latterly, owning the providers whose bills it pays. Its scale gives it genuine capabilities, in data, in care coordination and in the ability to absorb the administrative complexity that defeats smaller organisations.

The same scale produces the objections. When one company insures fifty million people, employs ninety thousand physicians, processes a large share of all medical claims and administers prescription benefits for tens of millions, the ordinary checks that competition is supposed to provide operate weakly. The Change Healthcare outage demonstrated the point in the least ambiguous way available: a failure in one subsidiary stopped payments across a substantial part of the national health system for weeks, and no alternative infrastructure existed to take up the load.

The events of December 2024 and the year that followed marked a change in the company's position. The reaction to Brian Thompson's killing revealed a level of public anger that the industry had understood as background noise. The suspension of guidance and the change of leadership in May 2025 showed that the Medicare Advantage economics on which two decades of growth had rested were less secure than assumed. The criminal investigation into risk adjustment billing remains unresolved. The company that emerges from this period may be larger still, but the assumption that its growth is politically uncontested no longer holds.

Timeline

1974 Charter Med Incorporated founded in Minnetonka, Minnesota.
1977 Richard T. Burke forms United HealthCare Corporation.
1984 Company goes public.
1991 William W. McGuire becomes chief executive.
1995 MetraHealth acquired for about US$1.65 billion.
1998 Renamed UnitedHealth Group; Ingenix established.
2004 to 2006 Oxford Health Plans, PacifiCare and John Deere Health Care acquired.
2006 Stock option backdating scandal; McGuire departs and Stephen Hemsley becomes chief executive.
2009 Ingenix out-of-network database dismantled after a New York attorney general investigation; US$350 million settlement.
2011 Health services businesses consolidated under the Optum brand.
2015 Catamaran acquired for about US$12.8 billion, expanding Optum Rx.
2017 Hemsley becomes executive chairman; David Wichmann appointed chief executive.
2021 Andrew Witty appointed chief executive in February; Change Healthcare acquisition announced.
2022 Department of Justice challenge to the Change Healthcare deal fails; transaction closes; LHC Group agreed for US$5.4 billion.
2023 Headquarters moved to Eden Prairie; reporting on the nH Predict algorithm prompts class litigation.
2024 Change Healthcare ransomware attack in February affects data on about 100 million people; Brazilian operations sold; Brian Thompson killed on 4 December.
2025 Witty resigns and Hemsley returns as chief executive in May; guidance suspended; Department of Justice criminal inquiry reported in July; Scott Gottlieb joins the board in November.
2026 Massachusetts sues over MassHealth billing in May; US$3 billion artificial intelligence investment announced in June.