diff --git a/acmc/phen.py b/acmc/phen.py
index 68316f4aa54169364a3d1d4c4b8172f4d26b172f..f55111317299e2241002a598111e1c332d7f7c57 100644
--- a/acmc/phen.py
+++ b/acmc/phen.py
@@ -511,12 +511,12 @@ def validate(phen_dir: str):
     # create a list of all the concept set names defined in the concept set configuration
     concept_set_names = []
     for item in phenotype["concept_sets"]:
-        if item["name"] in concept_set_names:
-            validation_errors.append(
-                f"Duplicate concept set defined in concept sets {item['name'] }"
-            )
-        else:
-            concept_set_names.append(item["name"])
+        # if item["name"] in concept_set_names:
+        #     validation_errors.append(
+        #         f"Duplicate concept set defined in concept sets {item['name'] }"
+        #     )
+        # else:
+        concept_set_names.append(item["name"])
 
     # check codes definition
     for item in phenotype["concept_sets"]: