This study explores the impact of B Corp certification and its associated impact assessment on four case studies of small and medium-sized Brazilian companies certified as B Corps. The results reveal that although all companies had achieved high scores in the certification assessment, awarded on the basis of existing performance, they did not subsequently develop road maps for the future to improve their scores in the way which the B Corp Impact Assessment process endorses as one of the benefits of (...) certification. Their incremental changes are discussed in the light of the main motivations and expectations of these companies’ founders with regard to the certification. A central role of the B Corp certification for this group of companies was to improve their external reputation with investors, clients and consumers. They were not strongly driven to reshape internal processes in ways which would advance their scores in the impact assessment and which would tackle complex problems of corporate governance. Our findings contribute to enriching the discussion of stakeholder engagement and corporate governance in hybrid organizations and contribute to the emerging agenda on studying change over time in B Corps. (shrink)