Related parties and connected persons
Article 35 defines related parties. One example: a natural person and a company are related where the person directly or indirectly owns 50% or more of the company. Relatives, companies under common control and partners in the same partnership are also caught by the wider definition.
Connected persons are a separate group under Article 36, typically owners, directors and officers. Payments or benefits to them are deductible only to the extent they correspond with market value.