Hiring Your Payroll Provider As Your 401(k) TPA? Forget About It by grntrmd1800 | September 14, 2020 | UncategorizedAry Rosenbaum, Esq. of The Rosenbaum Law Firm P.C. recently published an updated article discussing these issues. Time and time again, we run into many problems when taking over plans from the large payroll providers.