Data recently posted on a federal website shows the cyberattack earlier this year at a UnitedHealth Group subsidiary affected 100 million patients — apparently a U.S. record.
The tally roughly matches the scope previously described by company Chief Executive Andrew Witty, who suggested during congressional testimony in May that data for 1 in 3 Americans could be affected by the hack.
The data breach at United’s subsidiary, called Change Healthcare, is by far the largest breach currently showing on the federal website. This list, however, doesn’t include incidents from more than two years ago, such as a 2015 breach at health insurer Anthem Inc. that affected data for about 79 million patients.
“We continue to notify potentially impacted individuals as quickly as possible, on a rolling basis, given the volume and complexity of the data involved and the review is in its final stages,” UnitedHealth Group said in a statement.
Minnetonka-based UnitedHealth Group owns UnitedHealthcare, the nation’s largest health insurer, and a fast-growing division called Optum, which acquired Change Healthcare for $13 billion in 2022.
Change Healthcare is involved in processing a large share of all health care claims and payments in the U.S. — roughly 15 billion health care transactions annually before the hack, affecting 1 in 3 patient records, according to federal officials.
The cyberattack forced UnitedHealth Group to shut down Change Healthcare’s system for processing medical claims, which created financial problems for hospitals and clinics across the country. For a time, the outage also snarled pharmacy counters, with some patients saying they struggled to fill prescriptions.
Earlier this year, the federal government opened an investigation to determine if a breach of protected health information occurred and whether UnitedHealth Group and Change Healthcare were in compliance with federal privacy, security and breach notification rules.