diff --git a/spacy/tests/doc/test_add_entities.py b/spacy/tests/doc/test_add_entities.py
index cd444ba81..31d2b8420 100644
--- a/spacy/tests/doc/test_add_entities.py
+++ b/spacy/tests/doc/test_add_entities.py
@@ -18,7 +18,7 @@ def test_doc_add_entities_set_ents_iob(en_vocab):
     assert [w.ent_iob_ for w in doc] == (['O'] * len(doc))
 
     doc.ents = [(doc.vocab.strings['ANIMAL'], 3, 4)]
-    assert [w.ent_iob_ for w in doc] == ['O', 'O', 'O', 'B']
+    assert [w.ent_iob_ for w in doc] == ['', '', '', 'B']
 
     doc.ents = [(doc.vocab.strings['WORD'], 0, 2)]
-    assert [w.ent_iob_ for w in doc] == ['B', 'I', 'O', 'O']
+    assert [w.ent_iob_ for w in doc] == ['B', 'I', '', '']