diff --git a/src/Microsoft.AspNet.Security.DataProtection/project.json b/src/Microsoft.AspNet.Security.DataProtection/project.json
index b12bf80f25..0c20fb3aee 100644
--- a/src/Microsoft.AspNet.Security.DataProtection/project.json
+++ b/src/Microsoft.AspNet.Security.DataProtection/project.json
@@ -3,7 +3,7 @@
   "frameworks": {
     "net45": {
         "frameworkAssemblies": {
-            "System.Security": "4.0.0-beta-*"
+            "System.Security": ""
         }
     },
     "aspnetcore50": {