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According to a new report from its Office of the Inspector General, the Social Security Administration received 89.7 million W-2s in the ten years from 2003 through 2012 that it cannot attribute to any legal worker in the United States because the name and Social Security Number on the W-2 do not match.

“We remain concerned about SSN misuse by noncitizens who are not authorized to work in the United States as well as the misuse of SSNs for identity theft purposes,” the IG says in the report.