158 Climatic Change (2015) 132:157–171 1 Introduction As the impacts of anthropogenic climate change have become increasingly evident (IPCC 2014), the issue of responsibility for these impacts has come to the fore. The concept of responsibility is central to the United Nations Framework Convention on Climate Change (UNFCCC), adopted at the Rio Earth Summit in 1992. Parties to that convention agreed that the industrialized nations—which had produced the lion’s share of greenhouse gas emissions—should take the lead in combating climate change Bon the basis of equity and in accordance with their common but differentiated responsibilities^ (United Nations 1992). The concept of Bdifferentiated^ responsibility signaled the recognition both that industrialized (Annex I) nations had produced most of the emissions, and that their wealth was intimately linked to the economic activities that produced those emissions (Shue 1999). The Kyoto Protocol thus focused attention on emission cuts by Annex I nations. This focus was consistent with the general ethical principle, as well as the common sense of daily life, that responsibility for a problem is assumed to fall on those who create it, particularly if they do so knowingly (Rawls 1971). Definitions of responsibility become intricate as people have divergent interpretations of what exactly the problem is, how to assess its costs, how to identify the responsible party or parties (particularly if many individuals or groups contributed), how fully they apprehended the consequences of their actions, and whether reasonable alternative actions were available to them. In the context of climate change, several competing views have been put forward about the allocation of responsibilities. The Brazilian Proposal, for example, analyzed by the UNFCCC Subsidiary Body for Scientific and Technical Advice (SBSTA), suggested that the burden of addressing climate change should be apportioned on the basis of cumulative historic emissions (Rive et al. 2006), rather than annual ones, because it is the former that drive global climate change. Differing allocation schemes dramatically alter the ranking of the most responsible nations (Fig. 1a–d). The nation-state framework for climate policymaking via the UNFCCC and scientific assessment via the IPCC has tended to obscure other ways at looking at the question of climate responsibility. One option is to focus on individuals. Noting that nations with similar total emissions (e.g., USA and China) may have very different per capita emissions (Baer et al. 2000), some commentators have proposed the concept of equal per capita allocation over time, with convergence toward a common per capita emission rate (Höhne et al. 2006). Others have suggested that the wealthiest individuals in the world, regardless of nationality, should bear a larger share of the burden (Chakravarty et al. 2009). Another option is to focus on industry. Recent lawsuits have drawn attention to the responsibilities of major emitting industries, particularly in transportation and electric power generation (Osofsky 2012). Shareholder resolutions and calls for institutional and individual divestment from the primary producers of coal, oil, and natural gas are giving rise to growing public discourse on the climate responsibilities of these fossil fuels companies (Lubber 2012; Oreskes 2013; Rockefeller Brothers Fund 2014). This paper focuses on the distinctive responsibilities of the investor-owned fossil fuel producers. First, we explore the conceptual territory of responsibility and the historical evidence that social change has resulted when notions of corporate responsibility have shifted in response to changing social values. We then present empirical evidence for the role of specific fossil fuel corporations, including many of the 90 largest industrial carbon producers whose products are responsible for nearly two-thirds of all known industrial greenhouse gas emissions since 1751 (Heede 2014). We emphasize that more than half of all industrial