Notwithstanding some visible debates, systematic evidence about the implications of greater corporate involvement in the social sector is sparse. We provide some of this evidence by examining one channel of corporate influence within the nonprofit sector–company sponsorship of philanthropic foundations. Our analysis shows that corporate foundations raise more funds and distribute grants with lower overhead than similar independent (i.e., non-corporate) foundations. However, their grantmaking is also more dispersed and less relational, and they tend to be governed by more ephemeral groups of officers and trustees. These findings suggest that corporate foundations benefit from having access to the resources of the companies that sponsor them but are constrained by their additional market-based motivations. The findings also update and refine what nonprofits might expect from corporate foundations relative to their more traditional independent counterparts.