This article explores the cultural characteristics of three open access (OA)‐friendly disciplines (physics, economics, and clinical medicine) and the ways in which those characteristics influence perceptions, motivations, and behaviors toward green OA. The empirical data are taken from two online surveys of European authors. Taking a domain analytic approach, the analysis draws on Becher and Trowler's (2001) and Whitley's (2000) theories to gain a deeper understanding of why OA repositories (OAR) play a particularly important role in the chosen disciplines. The surveys provided a unique opportunity to compare perceptions, motivations, and behaviors of researchers at the discipline level with the parent metadiscipline. It should be noted that participants were not drawn from a stratified sample of all the different subdisciplines that constitute each discipline, and therefore the generalizability of the findings to the discipline may be limited. The differential role of informal and formal communication in each of the three disciplines has shaped green OA practices. For physicists and economists, preprints are an essential feature of their respective OAR landscapes, whereas for clinical medics final published articles have a central role. In comparing the disciplines with their parent metadisciplines there were some notable similarities/differences, which have methodological implications for studying research cultures.