diff --git a/src/ert/storage/local_ensemble.py b/src/ert/storage/local_ensemble.py
index a82a0e2a0b7..a6f9acedbbd 100644
--- a/src/ert/storage/local_ensemble.py
+++ b/src/ert/storage/local_ensemble.py
@@ -643,7 +643,11 @@ def set_key_index(df, index: List[str]):
             )
 
             filtered_response = obs_ds.merge(responses_ds, join="left")
-            df = filtered_response.to_dataframe().reset_index().dropna()
+            df = (
+                filtered_response.to_dataframe()
+                .reset_index()
+                .dropna(subset="observations")
+            )
 
             index = ObservationsIndices[response_type]
             set_key_index(df, index)
@@ -702,7 +706,6 @@ def set_key_index(df, index: List[str]):
             and not drop_observations_without_response
             and any(not x.empty for x in observations_without_responses)
         ):
-
             for df in observations_without_responses:
                 df[long_dfs[0].columns[2:]] = np.nan
                 df.drop(columns=["name"], inplace=True)
diff --git a/tests/unit_tests/scenarios/test_summary_response.py b/tests/unit_tests/scenarios/test_summary_response.py
index 9309f0a7028..68df5e3d691 100644
--- a/tests/unit_tests/scenarios/test_summary_response.py
+++ b/tests/unit_tests/scenarios/test_summary_response.py
@@ -238,4 +238,4 @@ def test_that_mismatched_responses_gives_nan_measured_data(ert_config, prior_ens
     assert fopr_2.loc["STD"].iloc[1] == 0.05
     assert pd.isna(fopr_2.loc[0].iloc[1])
     assert pd.isna(fopr_2.loc[1].iloc[1])
-    assert pd.isna(fopr_1.loc[2].iloc[1])
+    assert pd.isna(fopr_2.loc[2].iloc[1])