Content Delivery Networks (CDNs) are major actors of the current telecommunication ecosystem. Our goal in this paper is to study their impact on other actors of the supply chain, especially on content innovation which is a key concern in the network neutrality debate where CDNs' role seems forgotten. Our findings indicate that vertically integrating a CDN helps Internet Service Providers (ISPs) collect fees from Content Providers (CPs), hence circumventing the interdiction of side payments coming from net-neutrality rules. However, this outcome is socially much better in terms of user quality and innovation fostering than having separate actors providing the access and CDN services: in the latter case double marginalization (both ISP and CDN trying to get some value from the supply chain) leads to suboptimal investments in CDN storage capacities and higher prices for CPs, resulting in reduced innovation.