diff --git a/backend/portal/serializers.py b/backend/portal/serializers.py
index fab276dc..c94ab187 100644
--- a/backend/portal/serializers.py
+++ b/backend/portal/serializers.py
@@ -238,7 +238,7 @@ def is_valid(self, *args, **kwargs):
             self.initial_data["target_populations"] = list(
                 (
                     map(int, self.initial_data["target_populations"].split(","))
-                    if "target_populations" in self.initial_data
+                    if self.initial_data.get("target_populations", "") != ""
                     else []
                 ),
             )