diff --git a/lib/controllers/v1/search_controller.js b/lib/controllers/v1/search_controller.js
index a6b636e9..7cd22fcc 100644
--- a/lib/controllers/v1/search_controller.js
+++ b/lib/controllers/v1/search_controller.js
@@ -78,11 +78,11 @@ SearchController.search = async req => {
     },
     // match the nested name_autocomplete field in the taxa index
     {
-      constant_score: {
-        filter: {
-          nested: {
-            path: "names",
-            ignore_unmapped: true,
+      nested: {
+        path: "names",
+        ignore_unmapped: true,
+        query: {
+          function_score: {
             query: {
               match: {
                 "names.name_autocomplete": {
@@ -92,10 +92,16 @@ SearchController.search = async req => {
                   operator: "and"
                 }
               }
-            }
+            },
+            script_score: {
+              script: {
+                source: "doc['names.is_valid'].size() == 0 || doc['names.is_valid'].value == false ? 0.5 : 2.0"
+              }
+            },
+            boost_mode: "replace",
+            score_mode: "max"
           }
-        },
-        boost: 2
+        }
       }
     },
     // boost exact matches in the taxa index