diff --git a/src/backend/core/authentication/backends.py b/src/backend/core/authentication/backends.py
index a4576916..41774d2c 100644
--- a/src/backend/core/authentication/backends.py
+++ b/src/backend/core/authentication/backends.py
@@ -66,7 +66,7 @@ class OIDCAuthenticationBackend(MozillaOIDCAuthenticationBackend):
         user_info = self.get_userinfo(access_token, id_token, payload)
         sub = user_info.get("sub")
 
-        if sub is None:
+        if not sub:
             raise SuspiciousOperation(
                 _("User info contained no recognizable user identification")
             )