diff --git a/chord_metadata_service/discovery/tests/constants.py b/chord_metadata_service/discovery/tests/constants.py
index de236dccc..1595e04a5 100644
--- a/chord_metadata_service/discovery/tests/constants.py
+++ b/chord_metadata_service/discovery/tests/constants.py
@@ -23,7 +23,7 @@
     "search": [
         {
             "section_title": "First Section",
-            "fields": ["sex", "age", "tissues"]
+            "fields": ["sex", "age", "tissues", "extraction_protocol"]
         }
     ],
     "fields": {
@@ -87,6 +87,16 @@
                 "units": "mm"
             }
         },
+        "extraction_protocol": {
+            "mapping": "experiment/extraction_protocol",
+            "mapping_for_search_filter": "individual/biosamples/experiment/extraction_protocol",
+            "title": "Experiment Extraction Protocol",
+            "description": "experiment extraction protocol",
+            "datatype": "string",
+            "config": {
+                "enum": ["NGS"]
+            },
+        },
     },
     "rules": {
         "count_threshold": 5,
diff --git a/chord_metadata_service/patients/tests/test_api.py b/chord_metadata_service/patients/tests/test_api.py
index 8c7c7e8ee..001e6862b 100644
--- a/chord_metadata_service/patients/tests/test_api.py
+++ b/chord_metadata_service/patients/tests/test_api.py
@@ -20,6 +20,8 @@
     CONFIG_PUBLIC_TEST_SEARCH_SEX_ONLY
 )
 from chord_metadata_service.discovery.types import DiscoveryConfig
+from chord_metadata_service.experiments import models as ex_m
+from chord_metadata_service.experiments.tests import constants as ex_c
 from chord_metadata_service.patients.models import Individual
 from chord_metadata_service.phenopackets import models as ph_m
 from chord_metadata_service.phenopackets.tests import constants as ph_c
@@ -380,13 +382,13 @@ def setUp(self):
             project=self.project_2,
         )
 
-        individuals = [
+        self.individuals = [
             c.generate_valid_individual(date_of_consent_range=(2020, 2023))
             for _ in range(self.num_individuals)
         ]
 
-        individual_objs = [Individual.objects.create(**individual) for individual in individuals]
-        ph_m.Biosample.objects.create(**ph_c.valid_biosample_1(Individual.objects.all()[0]))
+        individual_objs = [Individual.objects.create(**individual) for individual in self.individuals]
+        biosample = ph_m.Biosample.objects.create(**ph_c.valid_biosample_1(Individual.objects.all()[0]))
 
         for idx, individual in enumerate(individual_objs, 1):
             self.meta_data = ph_m.MetaData.objects.create(**ph_c.VALID_META_DATA_1)
@@ -396,6 +398,13 @@ def setUp(self):
                 meta_data=self.meta_data,
                 dataset=self.dataset,
             )
+            if idx == 1:
+                self.phenopacket.biosamples.add(biosample)
+                self.phenopacket.save()
+
+        instrument = ex_m.Instrument.objects.create(**ex_c.valid_instrument())
+        ex_m.Experiment.objects.create(**ex_c.valid_experiment(biosample, instrument, self.dataset, 1))
+        ex_m.Experiment.objects.create(**ex_c.valid_experiment(biosample, instrument, self.dataset, 2))
 
         random.seed(self.random_seed)
 
@@ -694,6 +703,15 @@ def test_public_filtering_mapping_for_search_filter(self):
         response_obj = response.json()
         self.assertEqual(1, response_obj["count"])
 
+    @override_settings(CONFIG_PUBLIC=CONFIG_PUBLIC_TEST_NO_THRESHOLD)
+    def test_public_filtering_two_experiments(self):
+        response = self.dt_authz_counts_get(f"/api/public?sex={self.individuals[0]['sex']}&extraction_protocol=NGS")
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        response_obj = response.json()
+        self.assertEqual(response_obj["count"], 1)
+        self.assertEqual(response_obj["biosamples"]["count"], 1)
+        self.assertEqual(response_obj["experiments"]["count"], 2)
+
     @override_settings(CONFIG_PUBLIC=DISCOVERY_CONFIG_TEST)
     def test_public_overview_sex(self):
         response = self.dt_authz_counts_get('/api/public_search_fields')