diff --git a/nerval/evaluate.py b/nerval/evaluate.py
index d82f35aaf36c6420071d74be1b180a1863d9ac42..6e2fef9d3631ce2545243188b68fb95224eb0a27 100644
--- a/nerval/evaluate.py
+++ b/nerval/evaluate.py
@@ -41,7 +41,7 @@ def get_position_label(label: str) -> str:
         pos = (
             NOT_ENTITY_TAG
             if label == NOT_ENTITY_TAG
-            else re.match(r"([BIESLU])-.{3,4}", label)[1]
+            else re.match(r"([BIESLU])-(.*)$", label)[1]
         )
     except TypeError:
         raise (Exception(f"The label {label} is not valid in BIOES/BIOLU format."))