diff --git a/conformance/failure_list_csharp.txt b/conformance/failure_list_csharp.txt
index e69de29b..922db94c 100644
--- a/conformance/failure_list_csharp.txt
+++ b/conformance/failure_list_csharp.txt
@@ -0,0 +1,4 @@
+Required.ProtobufInput.IllegalZeroFieldNum_Case_0
+Required.ProtobufInput.IllegalZeroFieldNum_Case_1
+Required.ProtobufInput.IllegalZeroFieldNum_Case_2
+Required.ProtobufInput.IllegalZeroFieldNum_Case_3