UnitedHealth says Change hackers stole health data on ‘substantial proportion of people in America’ The health tech giant handles health data for about half of all Americans Health insurance giant UnitedHealth Group has confirmed that a ransomware attack on its health tech subsidiary Change Healthcare earlier this year resulted in a huge theft of Americans’ private healthcare data. UnitedHealth said in a statement on Monday that a ransomware gang took files containing personal data and protected health info ...