Social Security numbers rarely fade away, even after they’re no longer being used as employee or student identifiers. That’s what the University of Washington learned when a computer hack put the names and Social Security numbers of more than 6,000 university staff, faculty and retirees at risk. The school had quit using the numbers seven years ago.

Yet, the SSNs were still housed on one server at the university’s Transportation Services and it was that computer that was hacked. While the breach occurred last December, those affected weren’t notified until last month. The reason? A university official described the hacked server as a “one-of-a-kind system” that made it difficult to identify exactly what information was affected.

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