This article analyses some of the legal issues that may arise from Public Private Innovation projects (PPI) with regard to State aid rules. The analysis reveals that public procurement is a not unproblematic means of compliance. Further, it is shown that the application of State aid law depends to a large extent on the way a PPI is organised and operated. The contract that forms the basis for a PPI is hence crucial to compliance with State aid law. For this reason, the article takes a closer look at potential State aid legal problems in PPI contracts.