Permanent establishment defined as a fixed place or agent authority creating taxable presence under the tax treaty. Permanent establishment is a fixed place of business where an enterprise's business is wholly or partly carried on, including places of management, branches, offices, factories, workshops, extraction sites and building sites of extended duration. Exclusions include facilities used solely for storage, display, certain stock maintenance, purchasing, information collection, and preparatory or auxiliary activities. An agent who habitually concludes contracts on behalf of an enterprise may create a permanent establishment unless limited to purchasing, while independent agents acting in the ordinary course do not.