When people think about tax enforcement, they rarely consider the IRS attacking payroll companies based on benefits they claimed for their clients, but this is happening with the Employee Retention Credit (“ERC”). What makes this more interesting is that the IRS is attacking both payroll companies and their clients thanks to their joint liability in certain situations. This reality sets the stage for primary battles against the IRS, accompanied by secondary clashes between payroll companies and their clients. The finger pointing has already started, and it will no doubt intensify as ERC enforcement escalates. This article analyzes four recent sources of IRS guidance about which parties will be on the hook when ERC claims get disallowed.