The purpose of the present article is to analyse South African listed companies’ public reporting in order to contribute to our understanding of how and why companies consider human rights. The empirical analysis is placed in the context of the increasing prominence of human rights as a business issue, premised in part on the activities of the United Nations (UN) Special Representative of the Secretary General (SRSG) on human rights and business. On the basis of a content analysis of the public reports of the top 100 companies listed on the Johannesburg Stock Exchange (JSE), we test hypotheses focused on the antecedents of companies’ demonstrated human rights due diligence, with particular reference to assumptions or findings of the SRSG and institutional theory. Some of our results are unexpected: there is little influence exerted by the sector and size of companies in our sample, and there is also an unexpectedly insignificant impact of company participation in the UN Global Compact and the JSE Socially Responsible Investment Index. On the other hand, a key predictor of human rights due diligence is an explicit leadership commitment, and important roles are also played by government regulations and stock exchange listing rules.