Wis. Admin. Code DWD § 80.67
A worker's compensation insurer shall notify the department and the Wisconsin compensation rating bureau in writing 30 days before the effective date of a change in its name. The insurer shall comply with the name change requirements in its state of domicile and in the state of Wisconsin. On or before the effective date of an approved name change, the insurer shall notify each of its employers insured under ch. 102, Stats., that the insurer's name is changed. Insurers shall notify employers by an endorsement to the employer's existing policy that states the insurer's new name. The insurer shall file a copy of the endorsement with the Wisconsin compensation rating bureau by personal service, facsimile, or certified mail at the same time that it provides notice to its employers insured under ch. 102, Stats.
Wis. Admin. Code Department of Workforce Development § DWD 80.67
The State of Wisconsin Office of the Commissioner of Insurance requires an advance notice of an insurer name change or reorganization. For further information, contact OCI at (608) 266-3585 or (800) 236-8517.