According to researchers from an identity protection company, publicly available tax forms have potentially put hundreds of thousands of identities at risk, publishing 472,866 Social Security Numbers in a five-year span. Charities unnecessarily included the numbers in 990 forms, which are part of public record.

The figures come from Identity Finder, which sifted through nearly 3 million 990s from 2001 to 2006 to dig up SSNs from scholarship recipients, donors, trustees and others associated with the nonprofits.

The largest group that had its numbers exposed were tax preparers who filed the documents and carelessly used SSNs rather than Preparer Tax Identification Numbers.

To protect yourself from potential exposure, you should not share your number with nonprofits you work with. If you’re applying for scholarships, it might be a good idea to look up the organization’s latest 990 on a site such as GuideStar.

To check whether an organization you’ve worked with has exposed SSNs, you can enter the organization’s Employer ID Number at the source link.

Tax Returns Expose SSNs to Public: Study [Identity Finder] (Thanks, Aaron!)

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