Empirical studies tend to treat oil nationalisations as basically discrete, sudden events, an approach that in some cases might be misleading and adds little to disentangle causality. On a contrary vein, we take a closer look at the 1970s nationalisation of Venezuela's oil industry and find evidence that this was a rather protracted affair, expanding over a 17‐year period. We argue that although the transfer of all assets to government hands was not completed until 1975, oil companies fully anticipated such move as early as 1958 and started to operate in a way compatible with a much shorter time horizon. Specifically, we use an estimate of the resource rent (defined as output price minus marginal extraction cost) to show a major shift in oil firms' implicit time horizon after 1958. Our results help to explain the rather weak causality link found in the data between oil nationalisations and price fluctuations.