diff --git a/Source/OpenTK/ContextHandle.cs b/Source/OpenTK/ContextHandle.cs
index 54e7b7c0..6c98ae30 100644
--- a/Source/OpenTK/ContextHandle.cs
+++ b/Source/OpenTK/ContextHandle.cs
@@ -52,7 +52,7 @@ namespace OpenTK
 
         public static implicit operator IntPtr(ContextHandle c)
         {
-            return c.handle;
+            return c != null ? c.handle : IntPtr.Zero;
         }
 
         public static implicit operator ContextHandle(IntPtr p)