diff --git a/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py b/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
index 9ea7125874..e5f27126e9 100644
--- a/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
+++ b/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
@@ -100,6 +100,7 @@ from xmodule.modulestore.exceptions import (
     DuplicateItemError,
     InsufficientSpecificationError,
     MultipleCourseBlocksFound,
+    MultipleLibraryBlocksFound,
     VersionConflictError
 )
 from xmodule.modulestore.split_mongo import BlockKey, CourseEnvelope