Corporate/collective moral responsibility is a thorny topic in business ethics and this paper argues that this is due a number of unacknowledged and connected epistemic issues. Firstly, CSR, Corporate Citizenship and many other research streams that are based on the assumption of collective and/or corporate moral responsibility are not compatible with Kantian ethics, consequentialism, or virtue ethics because corporate/collective responsibility violates the axioms and central hypotheses of these research programmes. Secondly, in the absence of a sound theoretical moral philosophical foundation, (...) business ethicists have based their ideas on legal and political epistemologies, yet still claim to be ethics-based. Thirdly, research is often driven by an intention to prove that a specific social goal is right, not by open and critical inquiry. Finally, today, corporate/collective moral responsibility is widely accepted as the Truth as most researchers are unaware of any issues because they are untrained in philosophy. The paper identifies the confusion about the epistemic basis as a major impediment for delivering a thick concept of the role of corporations as moral agents. Thus, the paper does not argue against corporate or collective agency as such, but points out an obvious but forgotten paradox: corporate and collective personhood cannot, at the moment at least, be epistemologically grounded in the field in which business ethics claims to operate: moral philosophy. (shrink)