A significant data breach at Yale New Haven Health, Connecticut's largest healthcare system, has affected over 5.5 million individuals, according to a legal notification submitted to the U.S. Department of Health and Human Services. The breach, which occurred in March, enabled malicious hackers to access and copy patients' personally identifiable information (PII) and some healthcare-related data. The type of stolen information varies among individuals but may include patient names, dates of birth, postal and email addresses, phone numbers, racial and ethnic data, and Social Security numbers. Additionally, details such as the types of patients and their medical record numbers were compromised. According to a statement on the healthcare system’s website, the extent of the breach is still under investigation, and the number of affected individuals could change. When reached by TechCrunch, a spokesperson for Yale New Haven Health declined to provide immediate comment. This incident marks the second major healthcare data breach reported this week, following Blue Shield of California's revelation that it had inadvertently shared health data of 4.7 million patients with Google over an extended period. Both breaches highlight the ongoing challenges and vulnerabilities in securing sensitive medical information, raising concerns about patient privacy and data security in the healthcare industry.