*In collaboration with Ana da Silva Ferreira In recent years, it has become common to see large investors and international funds linked to several clubs at the same time. At first glance, this phenomenon seems just another reflection of the globalization of football. However, there is a clear legal line that cannot be crossed: the same investor cannot exercise direct control or decisive influence over two clubs participating in the same European competition. This limitation is known as the 'multi-club ownership' rule. The reason is simple and easily understandable for any fan: to avoid conflicts of interest and guarantee the integrity of competitions organized by UEFA. If the same person, or entity, controls two clubs that could face each other, confidence in the results, in transfers between clubs and even in the strategic decisions of each team is compromised. The prohibition of simultaneous control is expressly provided for in UEFA regulations. Article 5 of the UEFA Champions League Regulations (as well as equivalent rules for the Europa League and Conference League) prescribes that no person, natural or legal, may have control or exert influence over more than one club participating in a European competition. What does it mean to have control or exert influence? Control or influence is considered to exist when there is, in particular: the holding of the majority of shareholders' voting rights; the right to appoint or dismiss the majority of members of the administrative, management or supervisory body of the club; control, as a shareholder, of the majority of voting rights under an agreement concluded with other shareholders; or the possibility of exerting a decisive influence on the club's decision-making. It is important to highlight that multiple ownership is not, in itself, illegal. An investor may hold shares in several clubs, as long as they do not exercise direct control or decisive influence over more than one club participating in the same competition. What happens if there are two clubs under the same control or influence? When UEFA identifies that two clubs are under the same control or dominant influence, it acts preventively: one of the clubs cannot compete. Exclusion can be avoided if one of the clubs demonstrates that it has ceased any form of control or dominant influence, for example by changing the shareholder structure or renouncing decision-making powers. To this end, clubs must prove that, by March 1st of the season in question, the criteria relating to the ownership of multiple clubs ('multi-club ownership criteria') are fully met, maintaining this compliance until the end of the competition season. If this compliance is not demonstrated, only one of the clubs will be able to participate in the competition in question, while the other will be declared ineligible for that edition of the competition, and may also be admitted to another European competition at a lower level (Europa League or Conference League). How do you determine which club will have to be excluded from the competition? To determine which club will be excluded, UEFA applies the following objective criteria (in descending order): the club that qualified for the most prestigious European competition remains; or the one that obtained the best classification in the respective championship; or, finally, the club whose national association occupied the highest position in the UEFA access ranking. UEFA has already applied this rule in practice. A recent example occurred with Crystal Palace, excluded from the 2025/26 UEFA Europa League because the same investor also controls Lyon, which is equally qualified. The English club lost its place in the Europa League and was relegated to the Conference League, while Lyon maintained its participation. From a legal point of view, this model works as a true risk test, evaluating who finances, who decides, who benefits and whether there is an alignment of interests between competing clubs. If there is a single dominant will, the rule is clear: two clubs cannot coexist under the same control in the same competition. For fans, the logic is intuitive: football accepts global investors, but does not tolerate someone playing on two sides of the field simultaneously. It is this balance - between capital, competition and credibility - that these standards seek to guarantee.