Permanent establishment rules define fixed place, agency and auxiliary activity exceptions to determine taxable presence. The Article defines permanent establishment as a fixed place of business and enumerates examples including management, branch, office, extraction sites, warehouses, sales outlets, installations and construction projects exceeding six months; it also treats provision of services or hire of plant and machinery for mineral oil prospecting or extraction as creating a permanent establishment. Exclusions cover solely preparatory or auxiliary activities (storage, display, stockholding, purchasing, information, advertising, research), subject to a saving where another fixed place exists for other purposes. Dependent agent activities giving rise to a permanent establishment are specified, while independent agents acting in the ordinary course of business are excepted, and mere corporate control does not alone create a permanent establishment.