At the heart of a franchise agreement and its compliance with European law, the franchisor’s know-how is of crucial importance. According to European block exemption regulations, know-how is defined as a confidential, substantial, and specific set of practical information not protected by a patent, derived from the franchisor’s experience. Its confidentiality is closely linked to the contract between the franchisor and its franchisees, and the latter cannot disclose it publicly. The notion of “substantial,” less precise by nature, refers to the actual value it brings to the franchisees, which can give rise to legal debates. As for its specific nature, it implies that this know-how must be formalized in manuals or documents provided to the franchisees, such as operational procedures or management tools. Although not subject to patent protection, know-how can be protected by a non-compete clause imposed on the franchisees upon signing the contract. The absence of effective know-how on the part of the franchisor can lead to the contract’s cancellation.