The Internal Revenue Service unwittingly released thousands of Social Security numbers, according to the government transparency group Public.Resource.org.

Members of nonprofit political organizations known as 527s were the victims as the IRS published highly sensitive information to a public database that reports the transactions of these groups.

Public.Resource.org founder Carl Malamud received a phone call and subsequent email from the IRS on June 18 ordering him to delete the information contained in business income tax return forms called 990-Ts, which Malamud received in mid-February. Public.Resource.org reposts publicly available government data in bulk.

Although the data was deleted the following day, the public domain site further investigated the extent of the problem. It determined that there were eight distinct privacy breaches, including the exposure of at least 2,319 Social Security numbers.

In a letter to a female IRS official and a male special agent with the inspector general, both unidentified, Malamud pointed out that no contacted IRS officials clarified if those who filed the 990-Ts had been notified of the privacy violations.

He further scolded the IRS’s lack of transparency and warned that the failure to immediately correct the issue would constitute a cover-up.

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