diff --git a/backend/data_import/celery_tasks.py b/backend/data_import/celery_tasks.py
index af1f45be..e5109164 100644
--- a/backend/data_import/celery_tasks.py
+++ b/backend/data_import/celery_tasks.py
@@ -61,12 +61,12 @@ def import_dataset(user_id, project_id, file_format: str, upload_ids: List[str],
 
     parser = create_parser(file_format, **kwargs)
     builder = create_builder(project, **kwargs)
-    reader = Reader(filenames=filenames, parser=parser, builder=builder)
     cleaner = create_cleaner(project)
+    reader = Reader(filenames=filenames, parser=parser, builder=builder, cleaner=cleaner)
     writer = Writer(batch_size=settings.IMPORT_BATCH_SIZE)
-    writer.save(reader, project, user, cleaner)
+    writer.save(reader, project, user)
     upload_to_store(temporary_uploads)
-    return {"error": writer.errors + errors}
+    return {"error": reader.errors + errors}
 
 
 def upload_to_store(temporary_uploads):
diff --git a/backend/data_import/pipeline/readers.py b/backend/data_import/pipeline/readers.py
index 40303f74..e9c7d9cd 100644
--- a/backend/data_import/pipeline/readers.py
+++ b/backend/data_import/pipeline/readers.py
@@ -35,7 +35,7 @@ class Record:
         changed = len(label) != len(self.label)
         self._label = label
         if changed:
-            raise FileParseException(filename=self._data.filename, line_num=self._line_num, message=cleaner.message)
+            return FileParseException(filename=self._data.filename, line_num=self._line_num, message=cleaner.message)
 
     @property
     def data(self):
@@ -104,10 +104,11 @@ class Builder(abc.ABC):
 
 
 class Reader(BaseReader):
-    def __init__(self, filenames: List[FileName], parser: Parser, builder: Builder):
+    def __init__(self, filenames: List[FileName], parser: Parser, builder: Builder, cleaner: Cleaner):
         self.filenames = filenames
         self.parser = parser
         self.builder = builder
+        self.cleaner = cleaner
         self._errors: List[FileParseException] = []
 
     def __iter__(self) -> Iterator[Record]:
@@ -115,7 +116,11 @@ class Reader(BaseReader):
             rows = self.parser.parse(filename.full_path)
             for line_num, row in enumerate(rows, start=1):
                 try:
-                    yield self.builder.build(row, filename, line_num)
+                    record = self.builder.build(row, filename, line_num)
+                    maybe_error = record.clean(self.cleaner)
+                    if maybe_error:
+                        self._errors.append(maybe_error)
+                    yield record
                 except FileParseException as e:
                     self._errors.append(e)
 
@@ -123,4 +128,5 @@ class Reader(BaseReader):
     def errors(self) -> List[FileParseException]:
         """Aggregates parser and builder errors."""
         errors = self.parser.errors + self._errors
-        return errors
+        errors.sort(key=lambda error: error.line_num)
+        return [error.dict() for error in errors]
diff --git a/backend/data_import/pipeline/writers.py b/backend/data_import/pipeline/writers.py
index 5f4f8b53..4850fdfe 100644
--- a/backend/data_import/pipeline/writers.py
+++ b/backend/data_import/pipeline/writers.py
@@ -1,10 +1,9 @@
 import itertools
 from collections import defaultdict
-from typing import Any, Dict, List, Type
+from typing import List, Type
 
 from django.conf import settings
 
-from .exceptions import FileParseException
 from .readers import BaseReader, Record
 from examples.models import Example
 from label_types.models import CategoryType, LabelType, SpanType
@@ -45,19 +44,14 @@ class Examples:
 class Writer:
     def __init__(self, batch_size: int):
         self.examples = Examples(batch_size)
-        self._errors: List[FileParseException] = []
 
-    def save(self, reader: BaseReader, project: Project, user, cleaner):
+    def save(self, reader: BaseReader, project: Project, user):
         it = iter(reader)
         while True:
             try:
                 example = next(it)
             except StopIteration:
                 break
-            try:
-                example.clean(cleaner)
-            except FileParseException as err:
-                self._errors.append(err)
 
             self.examples.add(example)
             if self.examples.is_full():
@@ -66,36 +60,30 @@ class Writer:
         if not self.examples.is_empty():
             self.create(project, user)
             self.examples.clear()
-        self._errors.extend(reader.errors)
-
-    @property
-    def errors(self) -> List[Dict[Any, Any]]:
-        self._errors.sort(key=lambda e: e.line_num)
-        return [error.dict() for error in self._errors]
 
     def create(self, project: Project, user):
-        self.save_label(project)
-        ids = self.save_data(project)
-        self.save_annotation(project, user, ids)
+        self.save_label_type(project)
+        ids = self.save_example(project)
+        self.save_label(project, user, ids)
 
-    def save_label(self, project: Project):
+    def save_label_type(self, project: Project):
         labels = list(itertools.chain.from_iterable([example.create_label(project) for example in self.examples]))
         labels = list(filter(None, labels))
         groups = group_by_class(labels)
         for klass, instances in groups.items():
             klass.objects.bulk_create(instances, ignore_conflicts=True)
 
-    def save_data(self, project: Project) -> List[Example]:
+    def save_example(self, project: Project) -> List[Example]:
         examples = [example.create_data(project) for example in self.examples]
         return Example.objects.bulk_create(examples)
 
-    def save_annotation(self, project: Project, user, examples):
-        # Todo: move annotation class
+    def save_label(self, project: Project, user, examples):
         mapping = {}
         label_types: List[Type[LabelType]] = [CategoryType, SpanType]
         for model in label_types:
             for label in model.objects.filter(project=project):
                 mapping[label.text] = label
+
         annotations = list(
             itertools.chain.from_iterable(
                 [data.create_annotation(user, example, mapping) for data, example in zip(self.examples, examples)]