Permanent establishment rules define fixed place criteria, list preparatory exceptions, and treat dependent agents concluding contracts as creating PE. Permanent establishment is a fixed place of business through which an enterprise carries on business, including management, branch, office, factory, workshop and resource extraction sites. Construction sites and related supervisory activities create a permanent establishment only if they continue beyond a limited duration. Excluded are facilities or fixed places used solely for storage, display, delivery, stock maintenance for processing, purchasing, information collection, or other preparatory or auxiliary activities, including combinations whose overall character remains preparatory or auxiliary. Independent agents acting in the ordinary course do not create a permanent establishment, but dependent agents habitually authorized to conclude contracts in the enterprise's name do, unless limited to excluded activities.