OCC Handbook - Interpretation of RESPA Exemptions

In Reg Z and RESPA, investment property which will not be owner-occupied is considered business purpose. I'm referring to RESPA 3500.5(b)(2) and Reg Z 226.3(a)(1). During a recent internal review, the analysts used the current OCC Handbook as their guide and it included the following exception on page 2: <i>"Exemptions (24 CFR 3500.5(b)) Transactions exempt from RESPA include loans: For which the primary purpose is business, commercial, or agricultural (definition parallels Regulation Z, 12 CFR 226.3(a)(1)). However, a business purpose loan made to one or more persons, acting in an individual capacity (natural persons) to acquire, refinance, improve, or maintain a one-to-four family residential property used or to be used to rent or lease to other persons is a covered transaction. An action by a sole proprietorship is not considered to be conducted in an individual capacity."</i> What is the authority on which OCC makes this statement of exemption in their Exam Guidebook? The regulation was written by the Federal Reserve - not OCC.