diff --git a/metadata.yaml b/metadata.yaml
index 02f0584..9e26ed2 100644
--- a/metadata.yaml
+++ b/metadata.yaml
@@ -1,5 +1,7 @@
 homepage: "https://stape.io/"
 versions:
+  - sha: 6be12bc9a7dfd5d6a3a6a8865fe3131a2e348d98
+    changeNotes: Fix falsy customer identifiers.
   - sha: 6955b64a199a667d6af5112fd2d4f1e6b4d15b90
     changeNotes: Added support for external_attribution_data.
   - sha: 896519ddfb566753a546dcc7fe4d105155b4ee21
diff --git a/template.js b/template.js
index 367e667..3b271ed 100644
--- a/template.js
+++ b/template.js
@@ -375,7 +375,7 @@ function addUserIdentifiers(eventData, mappedData) {
   let mobileId;
   let thirdPartyUserId;
   let addressInfo;
-  let userIdentifiersMapped;
+  let userIdentifiersMapped = [];
   let userEventData = {};
   let usedIdentifiers = [];
 
@@ -388,13 +388,16 @@ function addUserIdentifiers(eventData, mappedData) {
     let userIdentifiers = [];
 
     data.userDataList.forEach((d) => {
-      let identifier = {};
-
-      identifier[d.name] = hashData(d.name, d.value);
-      identifier['userIdentifierSource'] = d.userIdentifierSource;
-
-      userIdentifiers.push(identifier);
-      usedIdentifiers.push(d.name);
+      const valueType = getType(d.value);
+      const isValidValue = ['undefined', 'null'].indexOf(valueType) === -1 && d.value !== '';
+      if(isValidValue) {
+        let identifier = {};
+        identifier[d.name] = hashData(d.name, d.value);
+        identifier['userIdentifierSource'] = d.userIdentifierSource;
+
+        userIdentifiers.push(identifier);
+        usedIdentifiers.push(d.name);
+      }
     });
 
     userIdentifiersMapped = userIdentifiers;
@@ -455,7 +458,7 @@ function addUserIdentifiers(eventData, mappedData) {
     });
   }
 
-  if (userIdentifiersMapped) {
+  if (userIdentifiersMapped.length) {
     mappedData.userIdentifiers = userIdentifiersMapped;
   }
 
diff --git a/template.tpl b/template.tpl
index 1ebe289..f531046 100644
--- a/template.tpl
+++ b/template.tpl
@@ -954,7 +954,7 @@ function addUserIdentifiers(eventData, mappedData) {
   let mobileId;
   let thirdPartyUserId;
   let addressInfo;
-  let userIdentifiersMapped;
+  let userIdentifiersMapped = [];
   let userEventData = {};
   let usedIdentifiers = [];
 
@@ -967,13 +967,16 @@ function addUserIdentifiers(eventData, mappedData) {
     let userIdentifiers = [];
 
     data.userDataList.forEach((d) => {
-      let identifier = {};
-
-      identifier[d.name] = hashData(d.name, d.value);
-      identifier['userIdentifierSource'] = d.userIdentifierSource;
-
-      userIdentifiers.push(identifier);
-      usedIdentifiers.push(d.name);
+      const valueType = getType(d.value);
+      const isValidValue = ['undefined', 'null'].indexOf(valueType) === -1 && d.value !== '';
+      if(isValidValue) {
+        let identifier = {};
+        identifier[d.name] = hashData(d.name, d.value);
+        identifier['userIdentifierSource'] = d.userIdentifierSource;
+
+        userIdentifiers.push(identifier);
+        usedIdentifiers.push(d.name);
+      }
     });
 
     userIdentifiersMapped = userIdentifiers;
@@ -1034,7 +1037,7 @@ function addUserIdentifiers(eventData, mappedData) {
     });
   }
 
-  if (userIdentifiersMapped) {
+  if (userIdentifiersMapped.length) {
     mappedData.userIdentifiers = userIdentifiersMapped;
   }