diff --git a/litellm/llms/bedrock/files/transformation.py b/litellm/llms/bedrock/files/transformation.py
index 29ad1a8f7c4..cb10c2384cd 100644
--- a/litellm/llms/bedrock/files/transformation.py
+++ b/litellm/llms/bedrock/files/transformation.py
@@ -375,11 +375,15 @@ def _json_object(value: object) -> Mapping[str, object] | None:
     return value if isinstance(value, dict) else None
 
 
-def _batch_record_shape_problem(record: object) -> str | None:
-    record_object: Final = _json_object(record)
-    if record_object is None:
-        return "is not a JSON object"
-    body: Final = _json_object(record_object.get("body"))
+def _batch_json_object(line_number: int, line: str) -> _OpenAIBatchRecord:
+    record: Final = _load_batch_line(line_number, line)
+    if _json_object(record) is None:
+        raise _batch_line_error(line_number, "is not a JSON object")
+    return record
+
+
+def _batch_body_problem(record: Mapping[str, object]) -> str | None:
+    body: Final = _json_object(record.get("body"))
     if body is None:
         return "has a body that is missing or not a JSON object"
     if "model" in body and not isinstance(body["model"], str):
@@ -388,8 +392,8 @@ def _batch_record_shape_problem(record: object) -> str | None:
 
 
 def _batch_input_line(line_number: int, line: str) -> _BatchInputLine:
-    record: Final = _load_batch_line(line_number, line)
-    problem: Final = _batch_record_shape_problem(record)
+    record: Final = _batch_json_object(line_number, line)
+    problem: Final = _batch_body_problem(record)
     if problem is not None:
         raise _batch_line_error(line_number, problem)
     return _BatchInputLine(line_number=line_number, record=record)
@@ -404,14 +408,15 @@ def _parse_batch_jsonl(file_content: str) -> tuple[_BatchInputLine, ...]:
     return tuple(_batch_input_line(line_number, line) for line_number, line in _non_blank_lines(file_content))
 
 
-def _first_batch_record_model(file_content: str) -> str | None:
-    first_line: Final = next(_non_blank_lines(file_content), None)
-    if first_line is None:
-        return None
-    try:
-        return _batch_input_line(*first_line).record.get("body", {}).get("model", "")
-    except BedrockError:
+def _batch_file_model(file_content: str) -> str | None:
+    records: Final = tuple(
+        _batch_json_object(line_number, line) for line_number, line in _non_blank_lines(file_content)
+    )
+    if not records:
         return None
+    body: Final = _json_object(records[0].get("body"))
+    model: Final = body.get("model") if body is not None else None
+    return model if isinstance(model, str) else ""
 
 
 def _batch_s3_object_name(model: str) -> str:
@@ -644,7 +649,7 @@ class BedrockFilesConfig(BaseAWSLLM, BaseFilesConfig):
         if purpose == "batch":
             ## 1. If jsonl, check if there's a model name
             file_content: Final = self._get_content_from_openai_file(extracted_file_data_content)
-            batch_model: Final = _first_batch_record_model(file_content)
+            batch_model: Final = _batch_file_model(file_content)
             if batch_model is not None:
                 return _batch_s3_object_name(batch_model)
 
diff --git a/tests/unit/llms/bedrock/files/test_bedrock_files_transformation.py b/tests/unit/llms/bedrock/files/test_bedrock_files_transformation.py
index 619bb36c7aa..c01c028c0db 100644
--- a/tests/unit/llms/bedrock/files/test_bedrock_files_transformation.py
+++ b/tests/unit/llms/bedrock/files/test_bedrock_files_transformation.py
@@ -4427,13 +4427,33 @@ class TestMalformedBatchJsonl:
         assert exc_info.value.status_code == 400
         assert "line 3" in exc_info.value.message
 
-    def test_object_name_inference_still_falls_back_for_a_non_json_file(self):
-        from litellm.llms.bedrock.files.transformation import BedrockFilesConfig
+    @pytest.mark.parametrize("content_type", ["application/jsonl", "application/x-jsonl"])
+    @pytest.mark.parametrize(
+        "file_content",
+        [_MALFORMED_BATCH_JSONL, f"{_VALID_BATCH_LINE}\n\n[1, 2]\n".encode()],
+        ids=["invalid-json", "array-line"],
+    )
+    def test_create_file_rejects_a_malformed_line_before_uploading(self, content_type: str, file_content: bytes):
+        """application/x-jsonl is not on the batch MIME allowlist, so the upload skips conversion for it; the line
+        check must still run so the broken file is rejected instead of landing in S3 unchanged."""
+        from litellm.llms.bedrock.common_utils import BedrockError
 
-        object_name = BedrockFilesConfig().get_object_name(
-            {"content": b"just some text, not jsonl", "filename": "notes.txt"}, purpose="batch"
-        )
-        assert object_name.endswith("notes.txt")
+        with respx.mock as router:
+            any_request: Final = router.route()
+            with pytest.raises(BedrockError) as exc_info:
+                litellm.create_file(
+                    file=("batch.jsonl", file_content, content_type),
+                    purpose="batch",
+                    custom_llm_provider="bedrock",
+                    model="bedrock/amazon.nova-pro-v1:0",
+                    s3_bucket_name="litellm-batch-bucket",
+                    aws_region_name="us-west-2",
+                    aws_access_key_id="test-key-id",
+                    aws_secret_access_key="test-secret",
+                )
+        assert exc_info.value.status_code == 400
+        assert "line 3" in exc_info.value.message
+        assert not any_request.called
 
 
 _VALID_BATCH_RECORD: Final = json.loads(_VALID_BATCH_LINE)
@@ -4534,3 +4554,26 @@ async def test_create_file_accepts_a_batch_file_with_a_utf8_byte_order_mark(resp
     uploaded_record: Final = json.loads(put_route.calls.last.request.content)
     assert uploaded_record["recordId"] == _VALID_BATCH_RECORD["custom_id"]
     assert "/litellm-bedrock-files-amazon.nova-pro-v1-0-" in str(put_route.calls.last.request.url)
+
+
+@pytest.mark.usefixtures(httpx_transport.__name__)
+@pytest.mark.asyncio
+async def test_create_file_uploads_a_bedrock_format_batch_file_unchanged_when_its_mime_type_skips_conversion(
+    respx_mock: respx.MockRouter,
+) -> None:
+    put_route: Final = respx_mock.put(url__regex=r"https://s3\..+").respond(status_code=200)
+    bedrock_line: Final = json.dumps(
+        {"recordId": "req-1", "modelInput": {"messages": [{"role": "user", "content": [{"text": "Hello"}]}]}}
+    )
+
+    await litellm.acreate_file(
+        file=("batch.jsonl", f"{bedrock_line}\n".encode(), "application/x-jsonl"),
+        purpose="batch",
+        custom_llm_provider="bedrock",
+        s3_bucket_name="litellm-batch-bucket",
+        aws_region_name="us-west-2",
+        aws_access_key_id="test-access-key",
+        aws_secret_access_key="test-secret-key",
+    )
+
+    assert put_route.calls.last.request.content == f"{bedrock_line}\n".encode()