diff --git a/masque/file/gdsii.py b/masque/file/gdsii.py
index c323ecf..bd2c18a 100644
--- a/masque/file/gdsii.py
+++ b/masque/file/gdsii.py
@@ -411,8 +411,8 @@ def _annotations_to_properties(annotations: annotations_t, max_len: int = 126) -
             i = int(key)
         except ValueError as err:
             raise PatternError(f'Annotation key {key} is not convertable to an integer') from err
-        if not (0 < i < 126):
-            raise PatternError(f'Annotation key {key} converts to {i} (must be in the range [1,125])')
+        if not (0 < i <= 126):
+            raise PatternError(f'Annotation key {key} converts to {i} (must be in the range [1,126])')
 
         val_strings = ' '.join(str(val) for val in vals)
         b = val_strings.encode()