diff --git a/src/pyhf/pdf.py b/src/pyhf/pdf.py
index 2fd8b3c250..2b03da9020 100644
--- a/src/pyhf/pdf.py
+++ b/src/pyhf/pdf.py
@@ -770,7 +770,7 @@ def __init__(
         # build up our representation of the specification
         # Default to no POI name
         # https://github.com/scikit-hep/pyhf/issues/2327
-        poi_name = config_kwargs.pop("poi_name", "")
+        poi_name = config_kwargs.pop("poi_name", None)
         self._config = _ModelConfig(self.spec, **config_kwargs)
 
         modifiers, _nominal_rates = _nominal_and_modifiers_from_spec(