This article explores some of the ways in which marine genetic resources conceptually and normatively intersect with the concept and idea of commons. Through an analysis of the terminological ambiguities and semantic slippages characterizing the usage of the concept of commons in international law, the article addresses questions relation to the idea of global commons and to the multiple reciprocal mapping of concepts, categories and legal regimes (can the different existing inflections of the idea of commons be considered articulations of the same underlying concept? What legal categories are associated with the multiple inflections and articulations of the concept of commons? What legal regime(s) do they, or should they, refer to?) The analysis shows that the commons is best understood as a narrative, which is then unpacked, in order to illustrate how it links in multiple ways to an ensemble of legal categories and legal regimes. Finally, the article explores how do marine genetic resources fit in this conceptual and normative narrative, in order to map the applicable regimes, and examine whether, to which extent, and in what ways, marine genetic resources are, can and/or should be considered as commons.