The European Union has chosen centralized negotiation to ensure the supply of COVID-19 vaccines to its member states. Several international contracts have thus been concluded by the European Commission with pharmaceutical companies. Initially covered by confidentiality, three of them have nevertheless been made public following a dispute arising from the interpretation of obligations incumbent upon one of these laboratories. Their analysis allows determining that they are pre-purchase contracts, which may fall under the Vienna Convention on the International Sale of Goods, raising interpretation issues regarding the nature of the obligation to manufacture and deliver vaccine doses. Is it a result-based obligation as the Commission seems to assert, or is it an obligation of means? The clauses of 'Best reasonable efforts' prove particularly difficult to interpret here, especially as they are embedded in contracts characterized by a cooperation obligation on the part of the parties, within a European context of pharmaceutical deindustrialization. Faced with difficulties in fulfilling these contracts, contractualization thus shows its limits and some think that a more radical solution could be considered, that of infringing on the laboratory's intellectual property rights. To this end, several weapons available to public authorities are studied here. Some, like compulsory licensing or compulsory license, moderately infringe on the rights of the patent holder, while others are much more audacious and damaging to the industrialist, such as patent expropriation, requisition, or even nationalization. In any case, the question of sovereignty and the pharmaceutical industrial apparatus arises, and this is where decision-makers will have to work for the coming decades, as drugs and vaccines in particular have become diplomatic weapons.