Permanent establishment: definition and activity thresholds determine when foreign enterprises are taxable based on fixed place or dependent agent presence. Permanent Establishment is defined as a fixed place of business, including management, branches, offices, factories, workshops and extraction sites. Building sites, construction or installation projects and the furnishing of services through personnel on connected projects constitute a permanent establishment when they persist beyond the applicable temporal threshold. Exclusions apply for activities of a preparatory or auxiliary character (storage, display, stock for processing, purchasing, information collection). Agency rules deem an enterprise to have a permanent establishment where a representative habitually concludes contracts, maintains stock for delivery, or habitually obtains orders, subject to an independent-agent exception; insurance activities through non-independent agents also create a permanent establishment.