diff --git a/data-prepper-plugins/opensearch/src/main/java/org/opensearch/dataprepper/plugins/sink/opensearch/OpenSearchSink.java b/data-prepper-plugins/opensearch/src/main/java/org/opensearch/dataprepper/plugins/sink/opensearch/OpenSearchSink.java
index 7462d9dd78..f2d3f66619 100644
--- a/data-prepper-plugins/opensearch/src/main/java/org/opensearch/dataprepper/plugins/sink/opensearch/OpenSearchSink.java
+++ b/data-prepper-plugins/opensearch/src/main/java/org/opensearch/dataprepper/plugins/sink/opensearch/OpenSearchSink.java
@@ -309,7 +309,7 @@ private BulkOperation getBulkOperationForAction(final String action,
         }
 
 
-          final UpdateOperation.Builder<Object> updateOperationBuilder = (action.toLowerCase().equals(OpenSearchBulkActions.UPSERT.toString())) ?
+          final UpdateOperation.Builder<Object> updateOperationBuilder = (StringUtils.equals(action.toLowerCase(), OpenSearchBulkActions.UPSERT.toString())) ?
               new UpdateOperation.Builder<>()
                   .index(indexName)
                   .document(filteredJsonNode)