Abstract This paper studies the relationship between blockchain patents and firms' environmental and social performance. Using data from USPTO, we assess the effect of these patents on subcategories and aggregate grades for social and environmental dimensions. Our results show a negative main effect of blockchain‐related patents on social and environmental grades. However, this effect is moderated by company size and focus on R&D. We exploit the first legislation favorable to blockchain in the United States and find a positive effect of blockchain patents on environmental grades, showing a change in corporate behavior regarding the use of blockchain.