diff --git a/dvc/project.py b/dvc/project.py
index d1eb8d95c..96f6c35de 100644
--- a/dvc/project.py
+++ b/dvc/project.py
@@ -13,14 +13,6 @@ from dvc.cache import Cache
 from dvc.cloud.data_cloud import DataCloud
 
 
-class PipelineError(DvcException):
-    pass
-
-
-class StageNotInPipelineError(PipelineError):
-    pass
-
-
 class StageNotFoundError(DvcException):
     def __init__(self, path):
         msg = 'Stage file {} does not exist'.format(path)