Between the 1930s and the mid 1970s, it was commonly believed that in 1880 Karl Marx had proposed to dedicate to Charles Darwin a volume or translation of Capital but that Darwin had refused. The detail was often interpreted by scholars as having larger significance for the question of the relationship between Darwinian evolutionary biology and Marxist political economy. In 1973–4, two scholars working independently—Lewis Feuer, professor of sociology at Toronto, and Margaret Fay, a graduate student at Berkeley—determined simultaneously that (...) the traditional story of the proposed dedication was untrue, being based on a long-standing misinterpretation of the relevant correspondence. Between the two, and among several other scholars who became their respective allies, there developed a contest of authority and priority over the discovery. From 1975 to 1982, the controversy generated a considerable volume of spilled ink in both scholarly and popular publications. Drawing on previously unexamined archival resources, this article revisits the ‘case’ of the so-called ‘Darwin–Marx correspondence’ as an instance of the phenomenon of ‘multiple discovery’. A familiar occurrence in the natural sciences, multiple discovery is rarer in the humanities and social sciences. The present case of a priority dispute in the history of ideas followed patterns familiar from such disputes in the natural sciences, while also diverging from them in ways that shed light on the significance of disciplinary norms and research infrastructures. (shrink)