TIGTA recommended that the IRS change the status of the incomplete corrective actions from closed to open; develop formal written policies requiring submission of verifiable supporting documentation, including the Form 13872, Planned Corrective Action Status Update for TIGTA/GAO/MW/SD/TAS/REM Reports, when the corrective action is closed based on a management response to a TIGTA report; and provide additional training to staff for approving and closing corrective actions