Congress instructed the IRS to publish guidance on specific, limited issues related to the Employee Retention Credit (“ERC”). The IRS did so, first issuing regulations about its ability to recapture “erroneous refunds,” followed by additional regulations about its authority to grab related interest payments. These new rules, if they withstand scrutiny, will enhance the IRS’s enforcement capabilities. This article, the latest in a long series, explores four major ERC laws, two sets of regulations recently introduced by the IRS, various assessment periods applicable to ERC claims, and how they all interrelate.