diff --git a/Nexmo.Api.Test.Unit/SmsTest.cs b/Nexmo.Api.Test.Unit/SmsTest.cs
index 3c4c5c0b4..c1dfa9b16 100644
--- a/Nexmo.Api.Test.Unit/SmsTest.cs
+++ b/Nexmo.Api.Test.Unit/SmsTest.cs
@@ -236,5 +236,11 @@ public void TestDLRStruct()
             Assert.Equal(castObject.message_timestamp, System.DateTime.Parse("2020-01-01T12:00:00.000+00:00",ci));
 
         }
+
+        [Fact]
+        public void TestSendSmsWithSig()
+        {
+
+        }
     }
 }