This paper aims to analyze the extent to which inventive activity relies on open science. In other words, it investigates whether inventors utilize Open Access (OA) publications more than subscription-based ones, especially given that some inventors may lack institutional access. To achieve this, we utilized the (Marx, 2023) database, which contains citations of patents to scientific publications (Non-Patent References-NPRs). We focused on publications closely related to invention, specifically those cited solely by inventors within the body of patent texts. Our dataset was supplemented by OpenAlex data. The final sample comprised 961,104 publications cited in patents, of which 861,720 had a DOI. Results indicate that across all disciplines, OA publications are 38% more prevalent in patent citations (NPRs) than in the overall OpenAlex database. In biology and medicine, inventors use 73% and 27% more OA publications, respectively, compared to closed-access ones. Chemistry and computer science are also disciplines where OA publications are more frequently utilized in patent contexts than subscription-based ones.