The contribution of large companies is needed to decarbonize energy systems and the production of goods and services. Many companies respond actively to increasing pressures for contributing to the Paris Agreement's temperature goal, but is this more than greenwashing? A realistic assessment of companies' climate responses proves methodologically challenging. Previous literature highlighted a loose coupling of “symbolic” and “substantive” measures and organizational inertia for explaining companies' inaction toward deep decarbonization. We argue that such a distinction and isolated analyses of climate management activities are not enough for understanding the status and dynamics of corporate decarbonization. Instead, it requires a holistic approach that investigates how all these activities interrelate and how deeply they are integrated in the core business. In response to this gap, we propose to conceptualize the core business as a construct of the three dimensions management, value chain, and investments and present a novel framework for assessing corporate decarbonization on company-level. We test the framework in an exemplary study of three companies, emphasize the interdependencies between its elements and suggest four types of interrelations as focal areas for further research.