diff --git a/spacy/tests/tokens/test_merge.py b/spacy/tests/tokens/test_merge.py
new file mode 100644
index 000000000..944a62d0a
--- /dev/null
+++ b/spacy/tests/tokens/test_merge.py
@@ -0,0 +1,14 @@
+from __future__ import unicode_literals
+from spacy.en import English
+import numpy as np
+from spacy.attrs import HEAD
+
+
+def test_merge_hang():
+    text = 'through North and South Carolina'
+    EN = English(parser=False)
+    doc = EN(text, tag=True)
+    heads = np.asarray([[0, 3, -1, -2, -4]], dtype='int32')
+    doc.from_array([HEAD], heads.T)
+    doc.merge(18, 32, '', '', 'ORG')
+    doc.merge(8, 32, '', '', 'ORG')