Multinational companies are increasingly promoted as peacebuilders. Major arguments in support of such a position emphasise both interest-based and norm/socialisation-based factors. This article uses research on large mining MNCs in eastern DRC – those that, arguably, should be most likely to build peace according to the above positions – to engage critically with the business for peace agenda. First it demonstrates the limited peacemaking, as well as active peacebuilding, activities in broader society that companies undertake. Second, it finds that even those companies deemed most likely to build peace continue relying on hybrid (in)security practice. Third, this article calls for more reflexivity concerning the implications of the business for peace research agenda. While the latter might contribute to socialising businesses into contributions to peacebuilding, it also produces companies as legitimate authorities, despite their limitations as peacebuilders. As a result, new conflict and insecurity are produced, especially for/with those displaced from land and artisanal mining pits and left with no alternative livelihood options.