Confidential data of about 112,000 taxpayers inadvertently published by the IRS over the summer was mistakenly republished in late November and remained online until early December, the IRS disclosed Thursday.

Form 990-T data that was supposed to stay private had been taken offline but made its way back to the IRS site when a contractor uploaded an old file that still included most of the private information, a letter sent Thursday to congressional leaders said. The agency is required to make Form 990-Ts filed by nonprofit groups available online but is supposed to keep the form filed by individuals private; in both cases, the agency made that information available too.

An internal programming error caused the September release of private forms along with the ones filed by nonprofit groups, the letter said. This time, the contractor tasked with managing the database reuploaded the older file with the original data instead of a new file that filtered out the forms that needed to be kept private.

The IRS shared corrected data with the contractor on Nov. 23, but the old files had not been purged from their system. A third-party researcher alerted the IRS the files were back online on Dec. 1, and the IRS ordered the contractor to take them down immediately. Roughly 104,000 of the 106,000 forms disclosed in September were redisclosed this time.

Credit-sensitive information like Social Security numbers were not disclosed in the data, which was identical to what was accidentally released the first time. Some forms did contain names or business contact information that should have remained private. The IRS is in the process of contacting people impacted by the release.

The agency is reconsidering its relationship with the contractor Accenture on this project, according to a person familiar.
A spokesperson for Accenture could not be reached for comment.

“The IRS is continuing to review the situation to identify opportunities to establish additional controls and strengthen existing controls to protect taxpayer information,” said Treasury spokesperson John Rizzo.

The IRS is required by law to alert Congress when disclosure of more than 100,000 forms occurs.

The release of the records comes as House Ways and Means Committee Republicans plan on increased oversight of the agency once the GOP takes control of the chamber next month.
—With assistance from Naomi Jagoda.