(Reuters) – The February hack at UnitedHealth (NYSE:)’s Change Healthcare (NASDAQ:) unit affected the data of 100 million people, the U.S. health department’s website showed, making it the largest data breach in the country.
UnitedHealth did not immediately respond to a Reuters request for comment.
The Change Healthcare unit was breached by a hacking group called ALPHV, also known as “BlackCat.” UnitedHealth first reported the breach on Feb. 21.
In June, UnitedHealth issued a public notice about the ransomware hack as part of its requirements to notify the estimated one-third of the country whose private data may have been exposed in the attack.
