Ellis Carter discusses the Commensurate Test on the Charity Lawyer Website.
Ellis Carter, "Nonprofit Law Jargon Buster: The Commensurate Test," Charity Lawyer, August 16, 2010, accessed September 26, 2023
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Unfortunately, neither the Code nor the Treasury Regulations state what it means to be commensurate in scope. The IRS first introduced the concept in a relatively obscure 1964 ruling . . . Since then, the IRS has applied the test to reach the desired result, often without a clear legal rationale. As a result, the IRS' various applications of the commensurate test have muddied the waters so that no uniform understanding of what it means to be commensurate in scope has taken shape. Historically, the IRS has applied the commensurate in scope test differently in different contexts. . . .