diff --git a/src/Shared/Grpc/ProtoUtils.cs b/src/Shared/Grpc/ProtoUtils.cs
index 9ad4d2fdd..c3c0e45f7 100644
--- a/src/Shared/Grpc/ProtoUtils.cs
+++ b/src/Shared/Grpc/ProtoUtils.cs
@@ -788,7 +788,7 @@ internal static void ToEntityBatchRequest(
             FailureDetails = entityBatchResult.FailureDetails.ToProtobuf(),
             Actions = { entityBatchResult.Actions?.Select(a => a.ToOperationAction()) ?? [] },
             Results = { entityBatchResult.Results?.Select(a => a.ToOperationResult()) ?? [] },
-            CompletionToken = completionToken,
+            CompletionToken = completionToken ?? string.Empty,
             OperationInfos = { operationInfos ?? [] },
         };
     }