Thinktecture.IdentityModel (nuget): Helper library for identity & access control in .NET 4.0/WIF and .NET 4.5 (includes MVC4 and Web API support).
Keywords: WIF|WCF|ASP.NET|WebAPI|MVC|Security|Federation|Identity|Claims|Authentication|Authorization|CORS|OAuth|OAuth2|Bearer|JWT|Access|Control|Hawk|OpenID|Connect