diff --git a/server/src/main/java/au/org/aodn/ogcapi/server/core/service/ElasticSearch.java b/server/src/main/java/au/org/aodn/ogcapi/server/core/service/ElasticSearch.java
index af5d6647..315d9571 100644
--- a/server/src/main/java/au/org/aodn/ogcapi/server/core/service/ElasticSearch.java
+++ b/server/src/main/java/au/org/aodn/ogcapi/server/core/service/ElasticSearch.java
@@ -650,7 +650,40 @@ public SearchResult<FeatureGeoJSON> searchFeatureSummary(String collectionId, Li
             for (var hit : response.hits().hits()) {
                 EsFeatureCollectionModel hitFeatureCollection = hit.source();
                 if (hitFeatureCollection != null && hitFeatureCollection.getFeatures() != null) {
-                    features.addAll(hitFeatureCollection.toFeatureCollectionGeoJSON().getFeatures());
+                    // A collectionID may map to several dataset key. So we need to identify features with dataset keys. TO get a dataset key which sits in hit.properties.key. For example:
+                    // "properties": {
+                    //            "date": "2011-04",
+                    //            "collection": "4d3d4aca-472e-4616-88a5-df0f5ab401ba",
+                    //            "key": "mooring_acidification_realtime_qc.parquet"
+                    //          }
+                    String datasetKey = null;
+                    if (hitFeatureCollection.getProperties() != null) {
+                        Object keyObj = hitFeatureCollection.getProperties().get("key");
+                        if (keyObj != null) {
+                            datasetKey = keyObj.toString();
+                        }
+                    }
+
+                    List<FeatureGeoJSON> documentFeatures =
+                            hitFeatureCollection.toFeatureCollectionGeoJSON().getFeatures();
+
+                    for (FeatureGeoJSON feature : documentFeatures) {
+                        // add key in property field for each feature
+                        if (datasetKey != null) {
+                            Object featurePropsObj = feature.getProperties();
+
+                            if (featurePropsObj instanceof Map) {
+                                @SuppressWarnings("unchecked")
+                                Map<String, Object> featurePropsMap = (Map<String, Object>) featurePropsObj;
+                                featurePropsMap.put("key", datasetKey);
+                            } else {
+                                Map<String, Object> newPropsMap = new HashMap<>();
+                                newPropsMap.put("key", datasetKey);
+                                feature.setProperties(newPropsMap);
+                            }
+                        }
+                        features.add(feature);
+                    }
                 }
             }
 
diff --git a/server/src/test/java/au/org/aodn/ogcapi/server/service/ElasticSearchTest.java b/server/src/test/java/au/org/aodn/ogcapi/server/service/ElasticSearchTest.java
index 7447e40a..919e2b49 100644
--- a/server/src/test/java/au/org/aodn/ogcapi/server/service/ElasticSearchTest.java
+++ b/server/src/test/java/au/org/aodn/ogcapi/server/service/ElasticSearchTest.java
@@ -25,6 +25,7 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.*;
 
 public class ElasticSearchTest {
@@ -61,10 +62,22 @@ public void searchFeatureSummaryTest() throws IOException {
         featureCollectionProperties.put("key", "satellite_ghrsst_l4_gamssa_1day_multi_sensor_world.zarr");
         esFeatureCollection.setProperties(featureCollectionProperties);
         var coords = new ArrayList<List<List<BigDecimal>>>();
+        var esFeature = new EsFeatureModel();
+
+        // mock a single point [147.338884, -43.190779]
+        List<List<BigDecimal>> ring = new ArrayList<>();
+        List<BigDecimal> point = List.of(
+                new BigDecimal("147.338884"),
+                new BigDecimal("-43.190779")
+        );
+        ring.add(point);
+        coords.add(ring);
+
         var polygon = new EsPolygonModel();
         polygon.setCoordinates(coords);
-        var esFeature = new EsFeatureModel();
+
         esFeature.setGeometry(polygon);
+
         esFeatureCollection.setFeatures(List.of(esFeature));
 
         when(hit.source()).thenReturn(esFeatureCollection);
@@ -88,7 +101,18 @@ public void searchFeatureSummaryTest() throws IOException {
         assertNotNull(result);
         assertEquals(1, result.getCollections().size());
         assertEquals(1L, result.getTotal());
-        assertEquals(esFeature.toFeatureGeoJSON(), result.getCollections().get(0));
+        // validate geometry keeps same after adding key property
+        assertEquals(esFeature.toFeatureGeoJSON().getGeometry(),
+                result.getCollections().get(0).getGeometry());
+
+        // validate key is in properties
+        FeatureGeoJSON returnedFeature = result.getCollections().get(0);
+        @SuppressWarnings("unchecked")
+        Map<String, Object> featureProps = (Map<String, Object>) returnedFeature.getProperties();
+
+        assertTrue(featureProps.containsKey("key"));
+        assertEquals("satellite_ghrsst_l4_gamssa_1day_multi_sensor_world.zarr",
+                featureProps.get("key"));
     }