diff --git a/websocket-sharp/Net/HttpUtility.cs b/websocket-sharp/Net/HttpUtility.cs
index 1356bf1f..cac7fc49 100644
--- a/websocket-sharp/Net/HttpUtility.cs
+++ b/websocket-sharp/Net/HttpUtility.cs
@@ -470,14 +470,6 @@ namespace WebSocketSharp.Net
       return c >= '0' && c <= '9';
     }
 
-    private static bool isUnreserved (byte b)
-    {
-      return b == 42
-             || b == 45
-             || b == 46
-             || b == 95;
-    }
-
     private static bool isUnreserved (char c)
     {
       return c == '*'