This thesis attempts to resolve the deadlock to achieve an equitable division of taxes, and thereby internation equity. As the present tax laws were not negotiated, it is not considered here as fair. In this thesis it is proposed that an equitable division could be achieved through a division based on the levels of human development (combining Rawlsian schema and Sen’s capability approach). Therefore, it is argued that such a division would be equitable; because it would be based on entitlements (territorial claims), it would generate cooperation and thereby lead to greater efficiency. Importantly, this thesis establishes that the present tax treaties neither generate cooperation nor cohere with global welfare. Similarly, it is also found that the other institutions (OECD, IMF, WB and Dispute Settlement) related the tax regime presently do not promote development based on human capabilities. This could help developing countries to pursue a division favouring development (laws favouring development) and understand the institutions better suited to pursue such goals.

Le terme de « prix de transfert » désigne le prix des transactions conclues entre les filiales d’une même entreprise multinationale. La thèse traite, sous un angle essentiellement normatif, de la problématique de réglementation de ces prix, c'est-à-dire de la détermination du mode de partage optimal du profit d’un groupe entre ses filiales. La thèse s’attache tout d’abord à montrer l’effet de la réglementation des prix de transfert sur les décisions de production et d’investissement des entreprises, puis sur le bien-être mondial. Sur la base des résultats obtenus, les objectifs qu’un dictateur bienveillant international devrait assigner à ce type de réglementation sont ensuite établis. Ce double travail permet de tracer le contour d’un projet de réglementation optimale, fondé sur le concept d’équité inter-nations, et dont l’application conduirait à attribuer à chaque filiale sa valeur de Shapley dans un jeu préalablement défini. La thèse éclaire également le débat contemporain en proposant un protocole permettant de comparer le principe de pleine concurrence avec la méthode d’allocation forfaitaire. / The prices of the transactions set between subsidiaries of a multinational corporation are usually called « transfer prices ». The dissertation deals with the normative questions raised by the regulation of such prices, particularly the optimal way of distributing the profit of a multinational between its subsidiaries. The dissertation first shows how the transfer prices regulation can influence corporate production and investment decisions, thereby impacting worldwide welfare. Based upon these results, the objectives that an international benevolent dictator would pursue through such a regulation are then identified. This program allows for the sketching of an optimal transfer prices regulation, which relies strongly upon the inter-nation equity concept, and which application would grant each subsidiary its Shapley value in a certain game. The dissertation also makes a contribution to the current debate by proposing a protocol to compare the arm’s length principle with the formulary apportionment method.