1 files changed, 1 insertions, 10 deletions
diff --git a/src/mscorlib/shared/System/Threading/ExecutionContext.cs b/src/mscorlib/shared/System/Threading/ExecutionContext.cs
index 67857e9b11..a573af3383 100644
--- a/src/mscorlib/shared/System/Threading/ExecutionContext.cs
+++ b/src/mscorlib/shared/System/Threading/ExecutionContext.cs
@@ -44,7 +44,6 @@ namespace System.Threading
         }
     }
 
-    [Serializable]
     public sealed class ExecutionContext : IDisposable, ISerializable
     {
         internal static readonly ExecutionContext Default = new ExecutionContext();
@@ -71,15 +70,7 @@ namespace System.Threading
 
         public void GetObjectData(SerializationInfo info, StreamingContext context)
         {
-            if (info == null)
-            {
-                throw new ArgumentNullException(nameof(info));
-            }
-            Contract.EndContractBlock();
-        }
-
-        private ExecutionContext(SerializationInfo info, StreamingContext context)
-        {
+            throw new PlatformNotSupportedException();
         }
 
         public static ExecutionContext Capture()