diff --git a/src/Microsoft.AspNet.Session/SessionDefaults.cs b/src/Microsoft.AspNet.Session/SessionDefaults.cs
index 016eb77128..a498ca8e6e 100644
--- a/src/Microsoft.AspNet.Session/SessionDefaults.cs
+++ b/src/Microsoft.AspNet.Session/SessionDefaults.cs
@@ -7,7 +7,7 @@ namespace Microsoft.AspNet.Session
 {
     public static class SessionDefaults
     {
-        public static string CookieName = ".AspNet.Session";
-        public static string CookiePath = "/";
+        public static readonly string CookieName = ".AspNet.Session";
+        public static readonly string CookiePath = "/";
     }
 }
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