This Article establishes the criteria for defining 'related persons' and entities 'under common control'. It specifies that a natural person is related to a spouse, in-law, or relative up to the fourth degree. A natural person is considered related to a partnership or capital company if they, alone or with other related persons, control 50% or more of its income/capital rights or voting rights/value, respectively, either directly or indirectly. The Article also defines relatedness to agencies managing endowed properties based on beneficial interest. Entities are deemed under common control if the same person or related persons hold this 50% control threshold.