diff --git a/tests/commands/list_parts.sh b/tests/commands/list_parts.sh
index 93b4a720..6f63fb8d 100644
--- a/tests/commands/list_parts.sh
+++ b/tests/commands/list_parts.sh
@@ -38,4 +38,18 @@ list_parts_with_user() {
   listed_parts="$(echo -n "$listed_parts" | grep -v "InsecureRequestWarning")"
   log 5 "listed parts: $listed_parts"
   return 0
-}
\ No newline at end of file
+}
+
+list_parts_rest() {
+  if ! check_param_count_gt "bucket name, key, upload ID, callback, other params" 3 $#; then
+    return 1
+  fi
+  local bucket_name="$1" key="$2" upload_id="$3" callback="$4" params=("${@:5}")
+  local response
+
+  if ! response=$(send_rest_go_command_callback "200" "$callback" "-bucketName" "$bucket_name" "-objectKey" "$key" "-query" "uploadId=$upload_id" "${params[@]}" 2>&1); then
+    log 2 "error sending REST ListParts command or checking response: $response"
+    return 1
+  fi
+  return 0
+}
diff --git a/tests/drivers/complete_multipart_upload/complete_multipart_upload_rest.sh b/tests/drivers/complete_multipart_upload/complete_multipart_upload_rest.sh
index 985371b8..dfdf7b6c 100644
--- a/tests/drivers/complete_multipart_upload/complete_multipart_upload_rest.sh
+++ b/tests/drivers/complete_multipart_upload/complete_multipart_upload_rest.sh
@@ -149,7 +149,7 @@ test_complete_multipart_upload_unneeded_algorithm_parameter() {
   fi
   local checksum_type="$1" algorithm="$2"
   local file_and_bucket bucket_name mp_file_name
-  lcoal -a response_lines
+  local -a response_lines
 
   if ! file_and_bucket=$(setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME" 2>&1); then
     log 2 "error setting up file and bucket"
@@ -394,18 +394,54 @@ create_upload_part_copy_rest() {
   return 0
 }
 
+check_wrong_etag() {
+  if ! check_param_count_v2 "data file, part number, upload ID, etag" 4 $#; then
+    return 1
+  fi
+  local data_file="$1" part_number="$2" upload_id="$3" etag="$4"
+  local response xml_file
+
+  if ! response=$(get_file_name 2>&1); then
+    log 2 "error getting XML filename: $response"
+    return 1
+  fi
+  xml_file="$TEST_FILE_FOLDER/$response"
+
+  if ! get_xml_data "$data_file" "$xml_file"; then
+    log 2 "error getting XML data"
+    return 1
+  fi
+  if ! check_xml_element "$xml_file" "InvalidPart" "Code"; then
+    log 2 "code mismatch"
+    return 1
+  fi
+  if ! check_xml_element "$xml_file" "$upload_id" "UploadId"; then
+    log 2 "upload ID mismatch"
+    return 1
+  fi
+  if ! check_xml_element "$xml_file" "$part_number" "PartNumber"; then
+    log 2 "part number mismatch"
+    return 1
+  fi
+  if ! check_xml_element "$xml_file" "$etag" "ETag"; then
+    log 2 "etag mismatch"
+    return 1
+  fi
+  return 0
+}
+
 create_upload_finish_wrong_etag() {
   if ! check_param_count "create_upload_finish_wrong_etag" "bucket, key" 2 $#; then
     return 1
   fi
   local bucket="$1" key="$2"
-  local etag part_number response parts_payload result result_file error_file upload_id
+  local etag part_number response parts_payload result result_file upload_id
 
-  if ! response=$(get_file_names 2 2>&1); then
+  if ! response=$(get_file_name 2>&1); then
     log 2 "error getting file names: $response"
     return 1
   fi
-  read -r result_file error_file <<< "$response"
+  result_file="$response"
 
   etag="gibberish"
   part_number=1
@@ -416,7 +452,7 @@ create_upload_finish_wrong_etag() {
   upload_id="$response"
 
   parts_payload="<Part><ETag>$etag</ETag><PartNumber>$part_number</PartNumber></Part>"
-  if ! result=$(COMMAND_LOG="$COMMAND_LOG" BUCKET_NAME="$bucket" OBJECT_KEY="$key" UPLOAD_ID="$upload_id" PARTS="$parts_payload" OUTPUT_FILE="$TEST_FILE_FOLDER/$result_file" ./tests/rest_scripts/complete_multipart_upload.sh); then
+  if ! result=$(COMMAND_LOG="$COMMAND_LOG" BUCKET_NAME="$bucket" OBJECT_KEY="$key" UPLOAD_ID="$upload_id" PARTS="$parts_payload" OUTPUT_FILE="$TEST_FILE_FOLDER/$result_file" ./tests/rest_scripts/complete_multipart_upload.sh 2>&1); then
     log 2 "error completing multipart upload: $result"
     return 1
   fi
@@ -424,24 +460,64 @@ create_upload_finish_wrong_etag() {
     log 2 "complete multipart upload returned code $result: $(cat "$TEST_FILE_FOLDER/$result_file")"
     return 1
   fi
-  if ! get_xml_data "$TEST_FILE_FOLDER/$result_file" "$TEST_FILE_FOLDER/$error_file"; then
-    log 2 "error getting XML data"
+  if ! check_wrong_etag "$TEST_FILE_FOLDER/$result_file" "$part_number" "$upload_id" "$etag"; then
+    log 2 "error checking etag in error message"
     return 1
   fi
-  if ! check_xml_element "$TEST_FILE_FOLDER/$error_file" "InvalidPart" "Code"; then
-    log 2 "code mismatch"
+  return 0
+}
+
+complete_multipart_upload_overwrite_part() {
+  if ! check_param_count_v2 "bucket, key, file" 3 $#; then
     return 1
   fi
-  if ! check_xml_element "$TEST_FILE_FOLDER/$error_file" "$upload_id" "UploadId"; then
-    log 2 "upload ID mismatch"
+  local bucket="$1" key="$2" file="$3"
+  local response upload_id part_idx etag parts_payload=""
+  local -a parts
+
+  if ! response=$(split_file "$file" 4 2>&1); then
+    log 2 "error splitting file: $response"
     return 1
   fi
-  if ! check_xml_element "$TEST_FILE_FOLDER/$error_file" "$part_number" "PartNumber"; then
-    log 2 "part number mismatch"
+  read -r -a parts <<< "$response"
+  if ! response=$(create_multipart_upload_rest "$bucket" "$key" "" "parse_upload_id" 2>&1); then
+    log 2 "error creating multipart upload: $response"
     return 1
   fi
-  if ! check_xml_element "$TEST_FILE_FOLDER/$error_file" "$etag" "ETag"; then
-    log 2 "etag mismatch"
+  upload_id="$response"
+
+  if ! response=$(upload_part_rest "$bucket" "$key" "$upload_id" 1 "${parts[1]}" 2>&1); then
+    log 2 "error uploading part 2 as part 1: $response"
+    return 1
+  fi
+  for ((part_idx=1; part_idx<=${#parts[@]}; part_idx++)); do
+    if ! response=$(upload_part_rest "$bucket" "$key" "$upload_id" "$part_idx" "${parts[$((part_idx-1))]}" 2>&1); then
+      log 2 "error uploading part '$part_idx':  $response"
+      return 1
+    fi
+    etag="$response"
+    parts_payload+="<Part><ETag>$etag</ETag><PartNumber>$part_idx</PartNumber></Part>"
+  done
+  if ! response=$(complete_multipart_upload_rest "$bucket" "$key" "$upload_id" "$parts_payload" 2>&1); then
+    log 2 "error completing multipart upload: $response"
+    return 1
+  fi
+  if ! download_and_compare_file "$file" "$bucket" "$key" "${file}-copy"; then
+    log 2 "error downloading and comparing file"
+    return 1
+  fi
+  return 0
+}
+
+complete_multipart_upload_expect_invalid_part_error_callback() {
+  if ! check_param_count_v2 "bucket name, key, upload ID, parts payload, expected part number, expected etag" 6 $#; then
+    return 1
+  fi
+  local bucket_name="$1" key="$2" upload_id="$3" parts_payload="$4" expected_part_number="$5" expected_etag="$6"
+
+  if ! send_rest_command_expect_error_callback "BUCKET_NAME=$bucket_name OBJECT_KEY=$key UPLOAD_ID=$upload_id PARTS=$parts_payload" \
+      "./tests/rest_scripts/complete_multipart_upload.sh" "400" "InvalidPart" "One or more" "check_wrong_etag" "$expected_part_number" "$upload_id" "$expected_etag"; then
+    log 2 "error checking complete multipart upload command"
     return 1
   fi
   return 0
diff --git a/tests/drivers/file.sh b/tests/drivers/file.sh
index f35529fd..03e70c1b 100644
--- a/tests/drivers/file.sh
+++ b/tests/drivers/file.sh
@@ -162,17 +162,9 @@ setup_bucket_and_large_file_v2() {
   return 0
 }
 
-setup_bucket_and_large_file_v3() {
-  if ! check_param_count_ge_le "bucket env var, file size in MBs (optional)" 1 2 $#; then
-    return 1
-  fi
-
-  local response bucket_name file_name error
-  if ! response=$(setup_bucket_v3 "$1" 2>&1); then
-    log 2 "error setting up bucket: $response"
-    return 1
-  fi
-  bucket_name="$response"
+setup_large_file_v3() {
+  local file_size="$1"
+  local response file_name
 
   if ! response=$(get_file_name 2>&1); then
     log 2 "error getting file name: $response"
@@ -180,10 +172,33 @@ setup_bucket_and_large_file_v3() {
   fi
   file_name="$response"
 
-  if ! error=$(create_large_file "$file_name" "$2" 2>&1); then
-    log 2 "error creating large file: $error"
+  if ! response=$(create_large_file "$file_name" "$file_size" 2>&1); then
+    log 2 "error creating large file: $response"
     return 1
   fi
+  echo "$file_name"
+  return 0
+}
+
+setup_bucket_and_large_file_v3() {
+  if ! check_param_count_ge_le "bucket env var, file size in MBs (optional)" 1 2 $#; then
+    return 1
+  fi
+  local bucket_env_var="$1" file_size="$2"
+  local response bucket_name file_name error
+
+  if ! response=$(setup_bucket_v3 "$bucket_env_var" 2>&1); then
+    log 2 "error setting up bucket: $response"
+    return 1
+  fi
+  bucket_name="$response"
+
+  if ! response=$(setup_large_file_v3 "$file_size" 2>&1); then
+    log 2 "error setting up large file: $response"
+    return 1
+  fi
+  file_name="$response"
+
   echo "$bucket_name $file_name"
   return 0
 }
diff --git a/tests/drivers/head_object/head_object_rest.sh b/tests/drivers/head_object/head_object_rest.sh
index 69391bbf..cbaf6ca3 100644
--- a/tests/drivers/head_object/head_object_rest.sh
+++ b/tests/drivers/head_object/head_object_rest.sh
@@ -261,17 +261,24 @@ head_object_check_header_key_and_value() {
 }
 
 check_header_partial_content_response() {
-  if ! check_param_count_v2 "header data, part number, full object size, part size" 4 $#; then
+  if ! check_param_count_v2 "header data, part number, full object size, part one size, part size" 5 $#; then
     return 1
   fi
-  log 5 "header: $(cat "$1")"
-  starting_byte=$((($2-1)*$4))
-  ending_byte=$(($2*$4-1))
-  if [ "$3" -lt "$ending_byte" ]; then
-    ending_byte="$(($3-1))"
+  local header_data="$1" part_number="$2" full_object_size="$3" part_one_size="$4" part_size="$5"
+  local starting_byte ending_byte content_range_string result
+
+  log 5 "header: $(cat "$header_data")"
+  starting_byte=$(((part_number-1)*part_one_size))
+  ending_byte=$((part_number*part_one_size-1))
+  if [ "$full_object_size" -lt "$ending_byte" ]; then
+    ending_byte="$((full_object_size-1))"
   fi
-  content_range_string="bytes $starting_byte-$ending_byte/$3"
-  if ! result=$(check_for_header_key_and_value "$1" "Content-Range" "$content_range_string" 2>&1); then
+  if [ "$part_size" -ne "$((ending_byte-starting_byte+1))" ]; then
+    log 2 "mismatch between part size '$part_size' and byte range '$starting_byte'-'$ending_byte'"
+    return 1
+  fi
+  content_range_string="bytes ${starting_byte}-${ending_byte}/${full_object_size}"
+  if ! result=$(check_for_header_key_and_value "$header_data" "Content-Range" "$content_range_string" 2>&1); then
     log 2 "error checking for header key and value: $result"
     return 1
   fi
diff --git a/tests/drivers/list_multipart_uploads/list_multipart_uploads_rest.sh b/tests/drivers/list_multipart_uploads/list_multipart_uploads_rest.sh
index 7cdfdf0e..0d9d593a 100644
--- a/tests/drivers/list_multipart_uploads/list_multipart_uploads_rest.sh
+++ b/tests/drivers/list_multipart_uploads/list_multipart_uploads_rest.sh
@@ -86,15 +86,16 @@ get_next_values() {
   if ! check_param_count_v2 "data file" 1 $#; then
     return 1
   fi
+  local data_file="$1"
   local response next_key_marker next_upload_id_marker
 
-  if ! response=$(get_element_text "$1" "NextKeyMarker" 2>&1); then
+  if ! response=$(get_element_text "$data_file" "NextKeyMarker" 2>&1); then
     log 2 "error checking NextKeyMarker: $response"
     return 1
   fi
   next_key_marker="$response"
 
-  if ! response=$(get_element_text "$1" "NextUploadIdMarker" 2>&1); then
+  if ! response=$(get_element_text "$data_file" "NextUploadIdMarker" 2>&1); then
     log 2 "error checking NextUploadIdMarker: $response"
     return 1
   fi
@@ -109,17 +110,32 @@ list_multipart_uploads_get_check_next_values() {
   if ! check_param_count_ge_le "bucket, expected key, expected upload ID, next key (optional), next upload ID (optional)" 3 5 $#; then
     return 1
   fi
-  local query_val="max-uploads=1&uploads" response
-  if [ "$4" != "" ]; then
-    query_val+="&key-marker=$4"
+  local bucket="$1" expected_key="$2" expected_upload_id="$3" next_key="$4" next_upload_id="$5"
+  local query_val="max-uploads=1&uploads" response key_marker upload_id_marker
+  local -a response_lines
+
+  if [ -n "$next_key" ]; then
+    query_val+="&key-marker=${next_key}"
   fi
-  if [ "$5" != "" ]; then
-    query_val+="&upload-id-marker=$5"
+  if [ -n "$next_upload_id" ]; then
+    query_val+="&upload-id-marker=${next_upload_id}"
   fi
-  if ! response=$(send_rest_go_command_callback "200" "get_next_values" "-bucketName" "$1" "-query" "$query_val" 2>&1); then
+  if ! response=$(send_rest_go_command_callback "200" "get_next_values" "-bucketName" "$bucket" "-query" "$query_val" 2>&1); then
     log 2 "error sending multipart upload and checking key and upload ID vals"
     return 1
   fi
+  mapfile -t response_lines <<< "$response"
+  key_marker="${response_lines[0]}"
+  upload_id_marker="${response_lines[1]}"
+
+  if [ "$expected_key" != "$key_marker" ]; then
+    log 2 "expected key marker '$expected_key', was '$key_marker'"
+    return 1
+  fi
+  if [ "$expected_upload_id" != "$upload_id_marker" ]; then
+    log 2 "expected upload ID marker '$expected_upload_id', was '$upload_id_marker'"
+    return 1
+  fi
   return 0
 }
 
diff --git a/tests/drivers/list_parts/list_parts_rest.sh b/tests/drivers/list_parts/list_parts_rest.sh
index 95c07412..01cc0a03 100644
--- a/tests/drivers/list_parts/list_parts_rest.sh
+++ b/tests/drivers/list_parts/list_parts_rest.sh
@@ -50,7 +50,7 @@ check_part_list_rest() {
     log 2 "error getting file name: $file_name"
     return 1
   fi
-  if ! result=$(COMMAND_LOG="$COMMAND_LOG" BUCKET_NAME="$1" OBJECT_KEY="$2" UPLOAD_ID="$3" OUTPUT_FILE="$TEST_FILE_FOLDER/$file_name" ./tests/rest_scripts/list_parts.sh); then
+  if ! result=$(COMMAND_LOG="$COMMAND_LOG" BUCKET_NAME="$1" OBJECT_KEY="$2" UPLOAD_ID="$3" OUTPUT_FILE="$TEST_FILE_FOLDER/$file_name" ./tests/rest_scripts/list_parts.sh 2>&1); then
     log 2 "error listing multipart upload parts: $result"
     return 1
   fi
@@ -241,3 +241,54 @@ list_parts_check_with_marker_and_max_parts() {
   fi
   return 0
 }
+
+list_parts_check_part_ordering() {
+  if ! check_param_count_gt "data file, bucket, key, upload ID, pairs of part numbers/etags" 3 $#; then
+    return 1
+  fi
+  if [ "$(($# % 2))" -ne 0 ]; then
+    log 2 "must be an even param count"
+    return 1
+  fi
+  local data_file="$1" bucket="$2" key="$3" upload_id="$4" part_etag_pairs=("${@:5}")
+  local response
+  local -a parts
+
+  log 5 "data: $(cat "$data_file")"
+
+  if ! check_xml_element "$data_file" "$bucket" "ListPartsResult" "Bucket"; then
+    log 2 "error checking 'Bucket' element"
+    return 1
+  fi
+  if ! check_xml_element "$data_file" "$key" "ListPartsResult" "Key"; then
+    log 2 "error checking 'Key' element"
+    return 1
+  fi
+  if ! check_xml_element "$data_file" "$upload_id" "ListPartsResult" "UploadId"; then
+    log 2 "error checking 'UploadId' element"
+    return 1
+  fi
+  if ! response=$(get_element "$data_file" "ListPartsResult" "Part" 2>&1); then
+    log 2 "error getting parts: $response"
+    return 1
+  fi
+  mapfile -t parts <<< "$response"
+  if [ "${#parts[@]}" -ne "$((${#part_etag_pairs[@]}/2))" ]; then
+    log 2 "expected '$((${#part_etag_pairs[@]}/2))' parts, was '${#parts[@]}'"
+    return 1
+  fi
+  pair_idx=0
+  for part in "${parts[@]}"; do
+    if ! check_xml_element_inside_string "$part" "${part_etag_pairs[$pair_idx]}" "Part" "PartNumber"; then
+      log 2 "error checking 'PartNumber' element"
+      return 1
+    fi
+    ((pair_idx++))
+    if ! check_xml_element_inside_string "$part" "${part_etag_pairs[$pair_idx]}" "Part" "ETag"; then
+      log 2 "error checking 'PartNumber' element"
+      return 1
+    fi
+    ((pair_idx++))
+  done
+  return 0
+}
diff --git a/tests/drivers/rest.sh b/tests/drivers/rest.sh
index e36541d2..d3edd604 100644
--- a/tests/drivers/rest.sh
+++ b/tests/drivers/rest.sh
@@ -92,6 +92,7 @@ send_rest_command() {
     return 1
   fi
   local response output_file response_code
+  local -a env_var_array
 
   if [[ "$1" == *"OUTPUT_FILE"* ]]; then
     if ! response=$(echo -n "$1" | sed -n 's/^.*OUTPUT_FILE=\([^ ]*\).*$/\1/p' 2>&1); then
@@ -108,8 +109,8 @@ send_rest_command() {
   fi
   local env_array=("env" "COMMAND_LOG=$COMMAND_LOG" "OUTPUT_FILE=$output_file")
   if [ "$1" != "" ]; then
-    IFS=' ' read -r -a env_vars <<< "$1"
-    env_array+=("${env_vars[@]}")
+    IFS=' ' read -r -a env_var_array <<< "$1"
+    env_array+=("${env_var_array[@]}")
   fi
   # shellcheck disable=SC2068
   if ! response=$(${env_array[@]} "$2" 2>&1); then
@@ -130,9 +131,23 @@ send_rest_command_expect_error() {
   if ! check_param_count_v2 "env vars, script, response code, error, message" 5 $#; then
     return 1
   fi
+  local env_vars="$1" script="$2" response_code="$3" error="$4" message="$5"
+
+  if ! send_rest_command_expect_error_callback "$env_vars" "$script" "$response_code" "$error" "$message"; then
+    log 2 "error checking REST error with empty callback"
+    return 1
+  fi
+  return 0
+}
+
+send_rest_command_expect_error_callback() {
+  if ! check_param_count_gt "env vars, script, expected HTTP code, expected error, expected message, callback, params" 5 $#; then
+    return 1
+  fi
+  local env_vars="$1" script="$2" expected_http_code="$3" expected_error="$4" expected_message="$5" callback="$6" params=("${@:7}")
   local response response_lines response_code output_file
 
-  if ! response=$(send_rest_command "$1" "$2" 2>&1); then
+  if ! response=$(send_rest_command "$env_vars" "$script" 2>&1); then
     log 2 "error sending REST command: $response"
     return 1
   fi
@@ -140,10 +155,14 @@ send_rest_command_expect_error() {
   response_code="${response_lines[0]}"
   output_file="${response_lines[1]}"
 
-  if ! check_rest_expected_error "$response_code" "$output_file" "$3" "$4" "$5"; then
+  if ! check_rest_expected_error "$response_code" "$output_file" "$expected_http_code" "$expected_error" "$expected_message"; then
     log 2 "error checking REST error"
     return 1
   fi
+  if [ -n "$callback" ] && ! "$callback" "$output_file" "${params[@]}"; then
+    log 2 "callback error"
+    return 1
+  fi
   return 0
 }
 
diff --git a/tests/test_rest_head_object.sh b/tests/test_rest_head_object.sh
index 2758b9db..41af9758 100755
--- a/tests/test_rest_head_object.sh
+++ b/tests/test_rest_head_object.sh
@@ -88,16 +88,16 @@ source ./tests/drivers/string.sh
   assert_success
   part_size_one="$output"
 
-  run get_file_size "$part_one"
+  run get_file_size "$part_two"
   assert_success
   part_size_two="$output"
 
   run send_rest_go_command_callback "206" "check_header_partial_content_response" "-bucketName" "$bucket_name" "-objectKey" "$test_file" \
-    "-method" "HEAD" "-query" "partNumber=1" "--" "1" "$file_bytes" "$part_size_one"
+    "-method" "HEAD" "-query" "partNumber=1" "--" "1" "$file_bytes" "$part_size_one" "$part_size_one"
   assert_success
 
   run send_rest_go_command_callback "206" "check_header_partial_content_response" "-bucketName" "$bucket_name" "-objectKey" "$test_file" \
-    "-method" "HEAD" "-query" "partNumber=2" "--" "2" "$file_bytes" "$part_size_two"
+    "-method" "HEAD" "-query" "partNumber=2" "--" "2" "$file_bytes" "$part_size_one" "$part_size_two"
   assert_success
 }
 
diff --git a/tests/test_rest_list_parts.sh b/tests/test_rest_list_parts.sh
index 46fad97b..9cd4b701 100755
--- a/tests/test_rest_list_parts.sh
+++ b/tests/test_rest_list_parts.sh
@@ -84,3 +84,50 @@ source ./tests/setup.sh
   run list_parts_check_with_marker_and_max_parts "$bucket_name" "$file_name" "$upload_id" 1 4 0
   assert_success
 }
+
+@test "REST - ListParts - out of order" {
+  local etag_one etag_two etag_three
+
+  run setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME"
+  assert_success
+  read -r bucket_name file_name <<< "$output"
+
+  run create_multipart_upload_rest "$bucket_name" "$file_name" "" "parse_upload_id"
+  assert_success
+  upload_id=$output
+
+  run split_file "$TEST_FILE_FOLDER/$file_name" 3
+  assert_success
+  read -r -a parts <<< "$output"
+
+  run upload_part_rest "$bucket_name" "$file_name" "$upload_id" "7" "${parts[0]}"
+  assert_success
+  etag_one="$output"
+  log 5 "sha256sum: $(sha256sum "${parts[0]}")"
+
+  run upload_part_rest "$bucket_name" "$file_name" "$upload_id" "2" "${parts[0]}"
+  assert_success
+  etag_two="$output"
+
+  run upload_part_rest "$bucket_name" "$file_name" "$upload_id" "10000" "${parts[0]}"
+  assert_success
+  etag_three="$output"
+
+  run list_parts_rest "$bucket_name" "$file_name" "$upload_id" "list_parts_check_part_ordering" "--" "$bucket_name" "$file_name" "$upload_id" \
+    "2" "$etag_two" "7" "$etag_one" "10000" "$etag_three"
+  assert_success
+
+  offset=100
+  old=$(od -An -tu1 -N1 -j "$offset" "${parts[0]}")
+  new=$((old ^ 255))
+  printf "\\$(printf '%03o' "$new")" | dd of="${parts[0]}" bs=1 seek="$offset" conv=notrunc status=none
+  log 5 "sha256sum: $(sha256sum "${parts[0]}")"
+
+  run upload_part_rest "$bucket_name" "$file_name" "$upload_id" "7" "${parts[0]}"
+  assert_success
+  etag_one="$output"
+
+  run list_parts_rest "$bucket_name" "$file_name" "$upload_id" "list_parts_check_part_ordering" "--" "$bucket_name" "$file_name" "$upload_id" \
+    "2" "$etag_two" "7" "$etag_one" "10000" "$etag_three"
+  assert_success
+}
\ No newline at end of file
diff --git a/tests/test_rest_multipart.sh b/tests/test_rest_multipart.sh
index bcbfccc5..65c3ef71 100755
--- a/tests/test_rest_multipart.sh
+++ b/tests/test_rest_multipart.sh
@@ -64,17 +64,12 @@ source ./tests/drivers/upload_part/upload_part_rest.sh
 }
 
 # tags: curl,multipart,CompleteMultipartUpload,invalid-header,ETag
-@test "REST - complete upload - invalid part" {
-  run get_bucket_name "$BUCKET_ONE_NAME"
-  assert_success
-  bucket_name="$output"
+@test "REST - complete upload - finish with non-existent part" {
+  local bucket_name large_test_file
 
-  run get_file_name
-  assert_success
-  large_test_file="$output"
-
-  run setup_bucket_and_large_file_v2 "$bucket_name" "$large_test_file"
+  run setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME"
   assert_success
+  read -r bucket_name large_test_file <<< "$output"
 
   run create_upload_finish_wrong_etag "$bucket_name" "$large_test_file"
   assert_success
@@ -377,7 +372,7 @@ source ./tests/drivers/upload_part/upload_part_rest.sh
 
 # tags: curl,multipart,checksum,CompleteMultipartUpload,invalid-header,x-amz-checksum-type,x-amz-checksum-algorithm
 @test "REST - multipart - composite - incorrect crc32" {
-  run test_complete_multipart_upload_incorrect_checksum "COMPOSITE" "CRC32C"
+  run test_complete_multipart_upload_incorrect_checksum "COMPOSITE" "CRC32"
   assert_success
 }
 
@@ -475,3 +470,92 @@ source ./tests/drivers/upload_part/upload_part_rest.sh
   run complete_multipart_upload_empty_upload_id "$bucket_name" "$file_name" "$TEST_FILE_FOLDER/$file_name"
   assert_success
 }
+
+@test "REST - multipart overwrite" {
+  local bucket_name file_name
+
+  run setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME"
+  assert_success
+  read -r bucket_name file_name <<< "$output"
+
+  run complete_multipart_upload_overwrite_part "$bucket_name" "$file_name" "$TEST_FILE_FOLDER/$file_name"
+  assert_success
+}
+
+@test "REST - multipart - InvalidPart error returns correct etag" {
+  if [ "$DIRECT" == "true" ]; then
+    skip "https://github.com/versity/versitygw/issues/2525"
+  fi
+  local bucket_name file_name upload_id parts_payload bad_etag first_etag bad_parts_payload
+
+  run setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME"
+  assert_success
+  read -r bucket_name file_name <<< "$output"
+
+  run multipart_upload_rest_before_completion "$bucket_name" "$file_name" "$TEST_FILE_FOLDER/$file_name" 2
+  assert_success
+  read -r upload_id parts_payload <<< "$output"
+
+  bad_etag="00000000000000000000000000000000"
+  first_etag=${parts_payload#*<ETag>}
+  first_etag=${first_etag%%</ETag>*}
+  bad_parts_payload=${parts_payload/"<ETag>$first_etag</ETag>"/"<ETag>$bad_etag</ETag>"}
+
+  run complete_multipart_upload_expect_invalid_part_error_callback "$bucket_name" "$file_name" "$upload_id" "$bad_parts_payload" "1" "$bad_etag"
+  assert_success
+}
+
+@test "REST - multipart failure, then success" {
+  local bucket_name file_name upload_id parts_payload first_etag bad_parts_payload
+
+  run setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME"
+  assert_success
+  read -r bucket_name file_name <<< "$output"
+
+  run multipart_upload_rest_before_completion "$bucket_name" "$file_name" "$TEST_FILE_FOLDER/$file_name" 2
+  assert_success
+  read -r upload_id parts_payload <<< "$output"
+
+  first_etag=${parts_payload#*<ETag>}
+  first_etag=${first_etag%%</ETag>*}
+  bad_parts_payload=${parts_payload/"<ETag>$first_etag</ETag>"/"<ETag>00000000000000000000000000000000</ETag>"}
+
+  run complete_multipart_upload_rest "$bucket_name" "$file_name" "$upload_id" "$bad_parts_payload"
+  assert_failure
+
+  run complete_multipart_upload_rest "$bucket_name" "$file_name" "$upload_id" "$parts_payload"
+  assert_success
+}
+
+@test "REST - multipart abort isolation" {
+  local bucket_name file_one_name file_two_name key_name upload_id_one upload_id_two parts_payload_two
+
+  run setup_bucket_and_large_file_v3 "$BUCKET_ONE_NAME"
+  assert_success
+  read -r bucket_name file_one_name <<< "$output"
+
+  run setup_large_file_v3
+  assert_success
+  file_two_name="$output"
+
+  run get_file_name
+  assert_success
+  key_name="$output"
+
+  run multipart_upload_rest_before_completion "$bucket_name" "$key_name" "$TEST_FILE_FOLDER/$file_one_name" 2
+  assert_success
+  read -r upload_id_one _ <<< "$output"
+
+  run multipart_upload_rest_before_completion "$bucket_name" "$key_name" "$TEST_FILE_FOLDER/$file_two_name" 2
+  assert_success
+  read -r upload_id_two parts_payload_two <<< "$output"
+
+  run abort_multipart_upload_rest "$bucket_name" "$key_name" "$upload_id_one"
+  assert_success
+
+  run complete_multipart_upload_rest "$bucket_name" "$key_name" "$upload_id_two" "$parts_payload_two"
+  assert_success
+
+  run download_and_compare_file "$TEST_FILE_FOLDER/$file_two_name" "$bucket_name" "$key_name" "$TEST_FILE_FOLDER/${file_two_name}-copy"
+  assert_success
+}