Wis. Stat. § 72.34

Every person liable for transmitting to the estate or a beneficiary of a deceased employee or former employee an annuity, bonus, pension or other benefit under a retirement, deferred compensation or profit-sharing plan taxable under this chapter, directly or through a trust or fund created by the employer for such purpose, shall give notice of such obligation to the department within 30 days following the date of payment, or the date of the initial payment if more than one payment is forthcoming, to the estate or any beneficiary of such employee or former employee.