diff --git a/samples/KWebStartup/project.json b/samples/KWebStartup/project.json
index e7414d56e5..ab2f5706ee 100644
--- a/samples/KWebStartup/project.json
+++ b/samples/KWebStartup/project.json
@@ -17,8 +17,6 @@
         "System.Diagnostics.Tools": "4.0.0.0",
         "System.Globalization": "4.0.10.0",
         "System.IO": "4.0.0.0",
-        "System.IO.FileSystem": "4.0.0.0",
-        "System.IO.FileSystem.Primitives": "4.0.0.0",
         "System.Linq": "4.0.0.0",
         "System.Reflection": "4.0.10.0",
         "System.Resources.ResourceManager": "4.0.0.0",
diff --git a/src/Microsoft.AspNet.Hosting/project.json b/src/Microsoft.AspNet.Hosting/project.json
index 5181a9bdac..159032003b 100644
--- a/src/Microsoft.AspNet.Hosting/project.json
+++ b/src/Microsoft.AspNet.Hosting/project.json
@@ -18,8 +18,6 @@
         "System.ComponentModel": "4.0.0.0",
         "System.Diagnostics.Debug": "4.0.10.0",
         "System.IO": "4.0.0.0",
-        "System.IO.FileSystem": "4.0.0.0",
-        "System.IO.FileSystem.Primitives": "4.0.0.0",
         "System.Linq": "4.0.0.0",
         "System.Reflection": "4.0.10.0",
         "System.Runtime": "4.0.20.0",