This study analyzes the feasibility of optimal equilibrium between antitrust exigencies and patent law necessities, when it comes to transnational investments in energy and sustainability global market. In doing so, the study first briefs on the ambits encircling the several interconnected subject-matters of law and economy associated with its general topic. Having scrutinized the current state of antitrust-patent intersection at WTO forum, the study moves on towards landmark literature and national practices and precedents regarding the interactivity of antitrust policy and patent law. With that backset, the specific antitrust problems of foreign direct investment in the global market of energy and sustainability products are explored in details. Based on all the argumentations and analyses provided, the study proposes a solution to the antitrust problem of foreign direct investment vis-à-vis energy and sustainability patents. Using mathematical schemes for decision-making, the proposed solution aims at introducing a fuzzjective efficiency test implementation for energy and sustainability patents. Lastly, the study portrays the orbits, components, and participants of a functional constitutive structure in which such decision-makings are to be carried out.