diff --git a/src/Microsoft.AspNetCore.Mvc.Core/project.json b/src/Microsoft.AspNetCore.Mvc.Core/project.json
index 29c9e5586c..552e4431c2 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/project.json
+++ b/src/Microsoft.AspNetCore.Mvc.Core/project.json
@@ -51,12 +51,7 @@
     "System.Diagnostics.DiagnosticSource": "4.0.0-*"
   },
   "frameworks": {
-    "net451": {
-      "frameworkAssemblies": {
-        "System.Reflection": "",
-        "System.Runtime": ""
-      }
-    },
+    "net451": { },
     "netstandard1.3": {
       "imports": [
         "dotnet5.4",
diff --git a/src/Microsoft.AspNetCore.Mvc.Razor/project.json b/src/Microsoft.AspNetCore.Mvc.Razor/project.json
index 400292a1f4..a06406b72b 100644
--- a/src/Microsoft.AspNetCore.Mvc.Razor/project.json
+++ b/src/Microsoft.AspNetCore.Mvc.Razor/project.json
@@ -34,7 +34,7 @@
   "frameworks": {
     "net451": {
       "frameworkAssemblies": {
-        "System.Threading.Tasks": ""
+        "System.Threading.Tasks": { "type": "build" }
       }
     },
     "netstandard1.5": {
diff --git a/test/Microsoft.AspNetCore.Mvc.WebApiCompatShimTest/project.json b/test/Microsoft.AspNetCore.Mvc.WebApiCompatShimTest/project.json
index 002032e0cd..84c60b7f91 100644
--- a/test/Microsoft.AspNetCore.Mvc.WebApiCompatShimTest/project.json
+++ b/test/Microsoft.AspNetCore.Mvc.WebApiCompatShimTest/project.json
@@ -28,6 +28,7 @@
     },
     "net451": {
       "frameworkAssemblies": {
+        "System.Reflection": "",
         "System.Threading.Tasks": ""
       },
       "dependencies": {