Despite long-standing evidence linking fossil fuel combustion to the greenhouse house and climate change effects, and the growing advocacy for reductions and regulatory limits on their use, fossil fuel corporations remain hugely profitable and influential. While corporations might employ a number of strategies to maintain their successes, when scientific evidence links corporate activities directly to concomitant damages, a response strategy favoured by Big Tobacco to evidence of medical harms appears to have been similarly adopted by Big Oil to Intergovernmental Panel on Climate Change (IPCC) findings of global atmospheric harms. To examine some of these strategies in detail, a corpus is compiled from samples of strategy documents of three Big Oil corporations for the period corresponding to the third, fourth and fifth IPCC Assessment Reports. This corpus is statistically and linguistically analysed for representations and accounts by Big Oil for its activities and how, if at all, the scientific evidence is addressed linking fossil fuel extraction and use to the findings of the IPCC on climatic change and ecosystemic disruptions at global scale. By highlighting corporate response narratives to IPCC evidence, policy and decision-makers might develop more effective counter-narratives to facilitate scientific communications in this critical policy space.