The Michigan Court of Appeals reversed the Court of Claims and held that an assessment of additional franchise tax on a bank was invalid because the Department of Revenue had improperly calculated the tax base of the bank’s unitary business group (“UBG”). The Michigan Business Tax Act provides that, for a financial institution, the “tax base means the financial institution’s net capital.” The Department had calculated the UBG’s net capital by applying a statutory averaging formula (adding net capital at the close of the current tax year and the preceding four tax years, and dividing the resulting sum by five) to individual members of the group, and then adding the resulting sums together. The Court explained, however, that the relevant statute requires treating UBG members as one taxpayer for filing purposes, and that a UBG’s net capital is determined by adding together the net capital of the group members, making elimination adjustments for intramember investments, and then applying the statutory averaging provision to the UBG. TCF Nat’l Bank v. Dep’t of Treasury, Nos. 344892, 344906 (Mich. Ct. App. Dec. 12, 2019).