Concluding that Malpass dictated the outcome of this case, the court held that the petitioners' S corporations did not form a single-business entity and thus, the respondent correctly determined that petitioners were required to apply a separate apportionment percentage to each S corporation, depending on its unique property, payroll, and sales figures. Petitioner-Larry Winget was the sole shareholder of several subchapter S corporations. Most of the corporations operated exclusively within Michigan, but during the tax years at issue (2001 and 2002), two or three S corporations had multistate operations. "Petitioners determined their Michigan income tax liability by combining the property, payroll, and sales figures for all of the S corporations to calculate a single apportionment percentage." They applied this apportionment percentage to each of the S corporations. After reviewing petitioners' tax returns for tax years 2001 and 2002, respondent concluded that they should have calculated and applied separate apportionment percentages for each of the S corporations. The MTT ruled in respondent's favor. On appeal, petitioners argued that apportionment of "business income" under MCL 206.115 may be calculated by adding the property, payroll, and sales of multiple S corporations to establish a single property factor, a single payroll factor, and a single sales factor. The court disagreed. "Malprass stands for the proposition that 'Michigan law does not allow separate entities to be treated as a unitary business in the absence of some common ownership at the entity level, and that being owned by the same individual taxpayers is insufficient to trigger this relationship requirement.'" It was undisputed that petitioners' S corporations were legally separate and distinct business entities and that there was no common ownership at the entity level. Thus, the court affirmed the MTT's order affirming respondent's assessments for tax years 2001 and 2002.