Think your social security number's your own? Not so fast, somebody out there could have the same number as you.
San Diego firm ID Analytics has looked at 290 million social security numbers. They've found 40 million of them have more than one name attached to them.
And what's more, the IRS often finds out when the impostor pays taxes.
The Social Security Administration finds out for the same reason.
But the last to find out is often the person whose number has been taken.
More than 20 million Americans have more than one SSN associated with their name.