With the aim of understanding current problematizations of embryonic stem cell patenting this article rehearses the history of social entitlements related to reproductive material derived from women seeking care in institutions for reproductive health in Denmark. Our interest lies in the emergence of commercial exchange of material derived from embryos. Such exchange is characterized by contestation of the status of the embryo: is it a person or a commodity? To understand the modus operandi of the exchanges, we first explore how (...) the concepts of personhood and morality, of commodity and ownership tend to be related in the ideal type of capitalist exchange. Historical context then helps us understand the contingency of exchange systems. Historically Danish women have had much less influence on the dissemination of material derived from them than they do today. However, today their entitlements have also found their limits, in particular with respect to commercial transactions. We claim that, ironically, material derived from institutionally mediated reproduction gains unprecedented personhood from confrontation with a capitalist exchange form which potentially designates it as a mere commodity. (shrink)