The Public Utility Holding Company Act of 1935 (PUHCA) was a law that was passed by the United States Congress to facilitate regulation of electric utilities, by either limiting their operations to a single state, and thus subjecting them to effective state regulation, or forcing divestitures so that each became a single integrated system serving a limited geographic area. Another purpose of PUHCA was to keep utility holding companies engaged in regulated businesses from engaging in unregulated businesses. PUHCA required that Securities and Exchange Commission approval be obtained by a holding company prior to engaging in a non-utility business and that such businesses be kept separate from the regulated business(es).
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