diff --git a/src/main/java/com/amazonaws/services/neptune/export/ExportToS3NeptuneExportEventHandler.java b/src/main/java/com/amazonaws/services/neptune/export/ExportToS3NeptuneExportEventHandler.java
index f5342fd..282d237 100644
--- a/src/main/java/com/amazonaws/services/neptune/export/ExportToS3NeptuneExportEventHandler.java
+++ b/src/main/java/com/amazonaws/services/neptune/export/ExportToS3NeptuneExportEventHandler.java
@@ -313,15 +313,17 @@ private void uploadCompletionFileToS3(S3TransferManager transferManager,
         logger.info("Uploading completion file to {}", completionFileS3ObjectInfo.key());
 
         try {
-            UploadFileRequest uploadFileRequest = UploadFileRequest.builder()
-                    .source(completionFile)
-                    .putObjectRequest(PutObjectRequest.builder()
+            PutObjectRequest.Builder putObjectRequestBuilder = PutObjectRequest.builder()
                             .bucket(completionFileS3ObjectInfo.bucket())
                             .key(completionFileS3ObjectInfo.key())
-                            .expectedBucketOwner(expectedBucketOwner)
                             .metadata(S3ObjectInfo.createObjectMetadata(completionFile.length(), sseKmsKeyId))
-                            .tagging(createObjectTags(profiles))
-                            .build())
+                            .tagging(createObjectTags(profiles));
+            if (StringUtils.isNotBlank(expectedBucketOwner)) {
+                putObjectRequestBuilder = putObjectRequestBuilder.expectedBucketOwner(expectedBucketOwner);
+            }
+            UploadFileRequest uploadFileRequest = UploadFileRequest.builder()
+                    .source(completionFile)
+                    .putObjectRequest(putObjectRequestBuilder.build())
                     .build();
 
             FileUpload upload = transferManager.uploadFile(uploadFileRequest);
diff --git a/src/main/java/com/amazonaws/services/neptune/export/NeptuneExportService.java b/src/main/java/com/amazonaws/services/neptune/export/NeptuneExportService.java
index 8479914..697cf7f 100644
--- a/src/main/java/com/amazonaws/services/neptune/export/NeptuneExportService.java
+++ b/src/main/java/com/amazonaws/services/neptune/export/NeptuneExportService.java
@@ -257,14 +257,14 @@ public S3ObjectInfo execute() throws IOException {
     private void checkS3OutputIsEmpty() {
         S3Client s3 = S3Client.builder().build();
         S3ObjectInfo s3ObjectInfo = new S3ObjectInfo(outputS3Path);
-        ListObjectsResponse listing = s3.listObjects(
-                ListObjectsRequest.builder()
+        ListObjectsRequest.Builder listRequestBuilder = ListObjectsRequest.builder()
                         .bucket(s3ObjectInfo.bucket())
                         .prefix(s3ObjectInfo.key())
-                        .maxKeys(1)
-                        .expectedBucketOwner(expectedBucketOwner)
-                        .build()
-        );
+                        .maxKeys(1);
+        if (StringUtils.isNotBlank(expectedBucketOwner)) {
+            listRequestBuilder = listRequestBuilder.expectedBucketOwner(expectedBucketOwner);
+        }
+        ListObjectsResponse listing = s3.listObjects(listRequestBuilder.build());
 
         if (listing.hasContents()) {
             throw new IllegalStateException(String.format("S3 destination contains existing objects: %s. Set 'overwriteExisting' parameter to 'true' to allow overwriting existing objects.", outputS3Path));
@@ -297,12 +297,14 @@ private File downloadFile(S3TransferManager transferManager, String s3Path) {
         logger.info("Key   : " + configFileS3ObjectInfo.key());
         logger.info("File  : " + file);
 
-        DownloadFileRequest downloadRequest = DownloadFileRequest.builder()
-                .getObjectRequest(GetObjectRequest.builder()
+        GetObjectRequest.Builder getObjectRequestBuilder = GetObjectRequest.builder()
                         .bucket(configFileS3ObjectInfo.bucket())
-                        .key(configFileS3ObjectInfo.key())
-                        .expectedBucketOwner(expectedBucketOwner)
-                        .build())
+                        .key(configFileS3ObjectInfo.key());
+        if (StringUtils.isNotBlank(expectedBucketOwner)) {
+            getObjectRequestBuilder = getObjectRequestBuilder.expectedBucketOwner(expectedBucketOwner);
+        }
+        DownloadFileRequest downloadRequest = DownloadFileRequest.builder()
+                .getObjectRequest(getObjectRequestBuilder.build())
                 .destination(file.toPath())
                 .build();
 
diff --git a/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV1.java b/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV1.java
index bad4e46..752e231 100644
--- a/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV1.java
+++ b/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV1.java
@@ -231,14 +231,16 @@ private void uploadTrainingJobConfigurationFileToS3(String filename,
         S3ObjectInfo s3ObjectInfo = outputS3ObjectInfo.withNewKeySuffix(filename);
 
         try {
-            UploadFileRequest uploadFileRequest = UploadFileRequest.builder()
-                    .source(trainingJobConfigurationFile)
-                    .putObjectRequest(configureServerSideEncryption(PutObjectRequest.builder(), sseKmsKeyId, expectedBucketOwner)
+            PutObjectRequest.Builder putObjectRequestBuilder = configureServerSideEncryption(PutObjectRequest.builder(), sseKmsKeyId, expectedBucketOwner)
                             .bucket(s3ObjectInfo.bucket())
                             .key(s3ObjectInfo.key())
-                            .expectedBucketOwner(expectedBucketOwner)
-                            .tagging(ExportToS3NeptuneExportEventHandler.createObjectTags(profiles))
-                            .build())
+                            .tagging(ExportToS3NeptuneExportEventHandler.createObjectTags(profiles));
+            if (StringUtils.isNotBlank(expectedBucketOwner)) {
+                putObjectRequestBuilder = putObjectRequestBuilder.expectedBucketOwner(expectedBucketOwner);
+            }
+            UploadFileRequest uploadFileRequest = UploadFileRequest.builder()
+                    .source(trainingJobConfigurationFile)
+                    .putObjectRequest(putObjectRequestBuilder.build())
                     .build();
 
             FileUpload upload = transferManager.uploadFile(uploadFileRequest);
diff --git a/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV2.java b/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV2.java
index 0adcba7..fde3497 100644
--- a/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV2.java
+++ b/src/main/java/com/amazonaws/services/neptune/profiles/neptune_ml/NeptuneMachineLearningExportEventHandlerV2.java
@@ -232,14 +232,16 @@ private void uploadTrainingJobConfigurationFileToS3(String filename,
         S3ObjectInfo s3ObjectInfo = outputS3ObjectInfo.withNewKeySuffix(filename);
 
         try {
-            UploadFileRequest uploadFileRequest = UploadFileRequest.builder()
-                    .source(trainingJobConfigurationFile)
-                    .putObjectRequest(configureServerSideEncryption(PutObjectRequest.builder(), sseKmsKeyId, expectedBucketOwner)
+            PutObjectRequest.Builder putObjectRequestBuilder = configureServerSideEncryption(PutObjectRequest.builder(), sseKmsKeyId, expectedBucketOwner)
                             .bucket(s3ObjectInfo.bucket())
                             .key(s3ObjectInfo.key())
-                            .expectedBucketOwner(expectedBucketOwner)
-                            .tagging(ExportToS3NeptuneExportEventHandler.createObjectTags(profiles))
-                            .build())
+                            .tagging(ExportToS3NeptuneExportEventHandler.createObjectTags(profiles));
+            if (StringUtils.isNotBlank(expectedBucketOwner)) {
+                putObjectRequestBuilder = putObjectRequestBuilder.expectedBucketOwner(expectedBucketOwner);
+            }
+            UploadFileRequest uploadFileRequest = UploadFileRequest.builder()
+                    .source(trainingJobConfigurationFile)
+                    .putObjectRequest(putObjectRequestBuilder.build())
                     .build();
 
             FileUpload upload = transferManager.uploadFile(uploadFileRequest);