In his recently published seminar Life Death (1975–76), Derrida engages in a close reading of Heidegger’s refutation of the biologistic interpretation of Nietzsche. Derrida explains that, building on his interpretation of Nietzsche as the peak of metaphysics, Heidegger wishes to rescue the latter’s metaphysical discourse from its biologizing character. In this article, I argue that Derrida’s reading centres on the ontological regionalism undergirding Heidegger’s refutation. To develop this argument, I test the following three hypotheses. First, I show that the later exploration offered in Life Death draws on the schematic reading of Heidegger’s question of being provided in Of Grammatology (1967). Second, I explain that, for Derrida, through his refutation of Nietzsche’s supposed biologism, Heidegger reaffirms ontological regionalism in order to secure the whole interpretative system that interweaves together his reading of Nietzsche and Western metaphysics and his thinking of being. Finally, I highlight Derrida’s emphasis on the relentlessness of Heidegger’s denunciation of biologism. I demonstrate that, for Derrida, this can be explained as biology, which is a discourse on life and nature that since its beginnings touches on the blind point of regionalism.