In recent years, an increasing number of states have considered or adopted unitary/combined reporting tax regimes, including the District of Columbia, West Virginia, Wisconsin, Michigan, and Massachusetts – as this is a way for state Departments of Revenue to raise revenue and close perceived “tax loopholes.” Combined reporting brings unique and challenging issues, including unitary/ownership rules, apportionment rules, and tax attribute utilization rules.
Grant Thornton is a thought leader in the arena of combined reporting and has been published in the various articles listed below:

