This is a prepublication version of ‘Replicating Marx: a reply to Mohun’, Capital and Class No. 88, Spring 2006, pp 117-123. ISSN 0309 8168 Kliman (2001) showed that “simultaneist” interpretations – those which hold that Marx valued inputs and outputs simultaneously – contradict his exploitation theory of profit, while the temporal single-system interpretation (TSSI) conforms to it. Mohun, S. 2003. “On the TSSI and the Exploitation Theory of Profit,” Capital and Class 81, Autumn 2003, pp85-102. calls these demonstrations into question. This note defends them.