Privately-owned corporations make a major contribution to climate change. Heede (2014) tracked 63% of cumulative global carbon and methane emissions across a 260 year period to just 90 "carbon majors". Of these carbon majors, 31 were state-owned and 9 were nation-states, leaving 50 (55% of the majors) that were investor-owned corporations. Whether or not other corporations make a significant enough contribution to have obligations to desist & mitigate, these 50 clearly do. But how does such an obligation distribute, if it all, from the carbon major (which I assume to be a collective agent) to its members? Answering this question requires an account of corporate membership, and a story about the distribution of obligations in groups with complex internal structure. I argue that employees at all levels of the hierarchy have obligations--proportional to their roles --to make a contribution to the corporation's desisting in emitting, and mitigating its history of emissions.