The Missouri Supreme Court held that Missouri could impose its net income tax on Amway's sale of distributorships within the state. Amway contended that federal law prohibits the imposition of state income taxes on revenue derived from sales made by sales people in the state and delivered to the customer from outside the state. The Court held that the federal prohibition on state taxes applied only to tangible personal property and that an Amway distributorship did not fall into that category. Because the federal statute did not protect it, Amway was found to be subject to state net income tax on revenue from the sale of Amway distributorships.

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