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Affected: 80 million patient and employee records, potentially exposing names, dates of birth, Social Security numbers, email addresses, employment information and income data.
Cost: The data breach could cost Anthem well over $100 million, according to ZDNet.com, with some estimating $8 to $16 billion.
What happened: In January 2015, health care giant Anthem learned of a cyberattack on its IT system that occurred over several weeks starting in December 2014. The stolen information may have included personal information, but the company does not believe credit card or banking information was compromised.