diff --git a/CRM/Core/Payment/Backer.php b/CRM/Core/Payment/Backer.php
index f57503dee..aa2be1993 100644
--- a/CRM/Core/Payment/Backer.php
+++ b/CRM/Core/Payment/Backer.php
@@ -310,7 +310,6 @@ function processContribution($jsonString, &$contributionResult) {
       civicrm_api('contact', 'create', $contact);
     }
 
-    // process recurring or contribution
     if ($contactId) {
       $contributionResult['contactId']  = $contactId;
       // create additional contact if needed
@@ -340,49 +339,66 @@ function processContribution($jsonString, &$contributionResult) {
           sort($foundDupes);
           $additionalContactId = reset($foundDupes);
         }
-        else {
-          $dedupeParams = array(
-            'last_name' => $params['additional']['last_name'],
-            'first_name' => $params['additional']['first_name'],
-          );
-          $dedupeParams = CRM_Dedupe_Finder::formatParams($dedupeParams, 'Individual');
-          $foundDupes = CRM_Dedupe_Finder::dupesByRules(
-            $dedupeParams,
-            'Individual',
-            'Strict',
-            array(),
-            array(
-              array('table' => 'civicrm_contact', 'field' => 'sort_name', 'weight' => 10),
-            ),
-            10
-          );
-        }
         if ($additionalContactId) {
           $params['additional']['id'] = $additionalContactId;
-          // only process address
+          $otherLocationTypeId = array_search('Other', $locationType);
+          $addContact = array();
+
+          // check addr exists
           $blockValue = $params['additional']['address'][0];
           $blockValue['contact_id'] = $additionalContactId;
           CRM_Core_BAO_Address::valueExists($blockValue);
           if (empty($blockValue['id'])) {
-            $otherLocationTypeId = array_search('Other', $locationType);
-            $billingLocationTypeId = array_search('Billing', $locationType);
-            if ($otherLocationTypeId && $billingLocationTypeId) {
-              $existsBillingAddr = CRM_Core_DAO::singleValueQuery("SELECT id FROM civicrm_address WHERE location_type_id = '$billingLocationTypeId' AND contact_id = %1", array(
+            if ($otherLocationTypeId) {
+              $existsAddr = CRM_Core_DAO::singleValueQuery("SELECT id FROM civicrm_address WHERE contact_id = %1", array(
+                1 => array($additionalContactId, 'Integer')
+              ));
+              if ($existsAddr) {
+                $params['additional']['address'][0]['location_type_id'] = $otherLocationTypeId;
+              }
+            }
+            $addContact['address'] = $params['additional']['address'];
+          }
+
+          // check phone exists
+          $blockValue = $params['additional']['phone'][0];
+          $blockValue['contact_id'] = $additionalContactId;
+          CRM_Core_BAO_Phone::valueExists($blockValue);
+          if (empty($blockValue['id'])) {
+            if ($otherLocationTypeId) {
+              $existsPhone = CRM_Core_DAO::singleValueQuery("SELECT id FROM civicrm_phone WHERE contact_id = %1", array(
+                1 => array($additionalContactId, 'Integer')
+              ));
+              if ($existsPhone) {
+                $params['additional']['phone'][0]['location_type_id'] = $otherLocationTypeId;
+                $params['additional']['phone'][0]['is_primary'] = 0;
+              }
+            }
+            $addContact['phone'] = $params['additional']['phone'];
+          }
+
+          // check email exists
+          $blockValue = $params['additional']['email'][0];
+          $blockValue['contact_id'] = $additionalContactId;
+          CRM_Core_BAO_Email::valueExists($blockValue);
+          if (empty($blockValue['id'])) {
+            if ($otherLocationTypeId) {
+              $existsEmail = CRM_Core_DAO::singleValueQuery("SELECT id FROM civicrm_email WHERE contact_id = %1", array(
                 1 => array($additionalContactId, 'Integer')
               ));
-              if ($existsBillingAddr) {
-                CRM_Core_DAO::executeQuery("UPDATE civicrm_address SET location_type_id = '$otherLocationTypeId' WHERE id = %1", array(
-                  1 => array($existsBillingAddr, 'Integer')
-                ));
+              if ($existsEmail) {
+                $params['additional']['email'][0]['location_type_id'] = $otherLocationTypeId;
+                $params['additional']['email'][0]['is_primary'] = 0;
               }
             }
-            $addContact = array(
-              'version' => 3,
-              'id' => $additionalContactId,
-              'address' => $params['additional']['address'],
-              'log_data' => ts('Updated contact').'-'.ts('Backer Auto Import'),
-            );
-            // log exists
+            $addContact['email'] = $params['additional']['email'];
+          }
+
+          // only update contact when value different
+          if (!empty($addContact)) {
+            $addContact['id'] = $additionalContactId;
+            $addContact['version'] = 3;
+            $addContact['log_data'] = ts('Updated contact').'-'.ts('Backer Auto Import');
             civicrm_api('contact', 'create', $addContact);
           }
         }
@@ -394,7 +410,7 @@ function processContribution($jsonString, &$contributionResult) {
           $additionalContactId = $result['id'];
         }
 
-        if ($additionalContactId) {
+        if ($additionalContactId && $additionalContactId != $contactId) {
           $addContactParams = array(
             'version' => 3,
             'contact_id_a' => $contactId,
@@ -578,6 +594,9 @@ public static function formatContact($json, &$params) {
         2 => array($countryId, 'Integer'),
       ));
     }
+
+    // #40812#note-10 , do not remove recipient data in form data stage
+    $params['additional'] = array();
     $address = array(
       'country' => ($json['recipient']['recipient_country'] == 'TW') ? 'Taiwan' : '',
       'postal_code' => $json['recipient']['recipient_postal_code'] ? $json['recipient']['recipient_postal_code'] : '',
@@ -586,47 +605,41 @@ public static function formatContact($json, &$params) {
       'street_address' => $json['recipient']['recipient_address'] ? $json['recipient']['recipient_address'] : '',
       'location_type_id' => array_search('Home', $locationType),
     );
-    if (trim($json['recipient']['recipient_name']) == trim($json['user']['name'])) {
-      $params['address'][] = $address;
+    $addName = self::explodeName(trim($json['recipient']['recipient_name']));
+    if ($addName === FALSE) {
+      $addName= array(
+        '',    // sure name
+        $json['recipient']['recipient_name'], // given name
+      );
     }
-    else {
-      $params['additional'] = array();
-      $addName = self::explodeName(trim($json['recipient']['recipient_name']));
-      if ($addName === FALSE) {
-        $addName= array(
-          '',    // sure name
-          $json['recipient']['recipient_name'], // given name
-        );
-      }
-      $params['additional'] = array(
-        'contact_type' => 'Individual',
-        'last_name' => $addName[0],
-        'first_name' => $addName[1],
+    $params['additional'] = array(
+      'contact_type' => 'Individual',
+      'last_name' => $addName[0],
+      'first_name' => $addName[1],
+    );
+    if ($json['recipient']['recipient_contact_email'] && CRM_Utils_Rule::email(trim($json['recipient']['recipient_contact_email']))) {
+      $params['additional']['email'][0] = array(
+        'email' => trim($json['recipient']['recipient_contact_email']),
+        'location_type_id' => array_search('Home', $locationType),
+        'is_primary' => 1,
+        'append' => TRUE,
       );
-      if ($json['recipient']['recipient_contact_email'] && CRM_Utils_Rule::email(trim($json['recipient']['recipient_contact_email']))) {
-        $params['additional']['email'][0] = array(
-          'email' => trim($json['recipient']['recipient_contact_email']),
-          'location_type_id' => array_search('Home', $locationType),
-          'is_primary' => 1,
-          'append' => TRUE,
-        );
-      }
-      if (!empty($json['recipient']['recipient_cellphone'])) {
-        $params['additional']['phone'][0] = array(
-          'phone' => trim($json['recipient']['recipient_cellphone']),
-          'phone_type_id' => 5, // other 
-          'location_type_id' => array_search('Home', $locationType),
-          'is_primary' => 1,
-          'append' => TRUE,
-        );
-        $addPhone = self::validateMobilePhone(trim($json['recipient']['recipient_cellphone']));
-        if ($addPhone) {
-          $params['additional']['phone'][0]['phone_type_id'] = 2;
-          $params['additional']['phone'][0]['phone'] = $addPhone;
-        }
+    }
+    if (!empty($json['recipient']['recipient_cellphone'])) {
+      $params['additional']['phone'][0] = array(
+        'phone' => trim($json['recipient']['recipient_cellphone']),
+        'phone_type_id' => 5, // other
+        'location_type_id' => array_search('Home', $locationType),
+        'is_primary' => 1,
+        'append' => TRUE,
+      );
+      $addPhone = self::validateMobilePhone(trim($json['recipient']['recipient_cellphone']));
+      if ($addPhone) {
+        $params['additional']['phone'][0]['phone_type_id'] = 2;
+        $params['additional']['phone'][0]['phone'] = $addPhone;
       }
-      $params['additional']['address'][0] = $address;
     }
+    $params['additional']['address'][0] = $address;
   }
 
   public static function formatRecurring($json, &$params) {
diff --git a/tests/phpunit/CRM/Core/Payment/BackerTest.php b/tests/phpunit/CRM/Core/Payment/BackerTest.php
index e62b50acf..1d21005af 100644
--- a/tests/phpunit/CRM/Core/Payment/BackerTest.php
+++ b/tests/phpunit/CRM/Core/Payment/BackerTest.php
@@ -536,20 +536,26 @@ function testBackerIPN(){
     $this->assertEquals($formatted['phone'][0]['phone'], $result['values'][$result['id']]['phone']);
   }
 
-  function testBackerAdditionAddress(){
+  function testBackerAdditionalContact(){
     $now = time();
     $contributionResult = NULL;
 
-    // prepare data
+    // case 1, this should create additional contact
     $json = json_decode($this->_json[1], TRUE);
-    $json['recipient']['recipient_name'] = '王小明';
+    $json['transaction']['trade_no'] = CRM_Utils_String::createRandom(15);
+    $json['user']['id'] = mt_rand(100000, 999999);
+    $json['user']['email'] = 'admintest.main1@eaxmple.com';
+    $json['user']['name'] = '張小弟';
+    $json['user']['cellphone'] = '+886912445667';
+    $json['recipient']['recipient_name'] = '張大媽';
+    $json['recipient']['recipient_contact_email'] = 'admintest.other1@eaxmple.com';
+    $json['recipient']['recipient_cellphone'] = '0933444555';
     $json = json_encode($json);
     $formatted = CRM_Core_Payment_Backer::formatParams($json);
 
-    // run
-    $createdContributionId = $this->_processor->processContribution($json, $contributionResult);
+    $this->_processor->processContribution($json, $contributionResult);
     $createdContributionId = $contributionResult['contributionId'];
-    $this->assertNotEmpty($createdContributionId, "In line " . __LINE__);
+    $this->assertNotEmpty($createdContributionId, "Contribution not created. In line " . __LINE__);
     $contactId = CRM_Core_DAO::getFieldValue('CRM_Contribute_DAO_Contribution', $createdContributionId, 'contact_id');
 
     $params = array(
@@ -561,18 +567,110 @@ function testBackerAdditionAddress(){
     $this->assertAPISuccess($result);
     $this->assertGreaterThan(0 , $result['count'], 'Additional contact count should greater than zero. In line '.__LINE__);
     $additionalContact = reset($result['values']);
-    $additionalContactId = $additionalContact['contact_id'];
+    $additionalContactId1 = $additionalContact['contact_id'];
     $this->assertEquals($formatted['additional']['address'][0]['street_address'], $additionalContact['street_address']);
+    $this->assertEquals($formatted['additional']['phone'][0]['phone'], $additionalContact['phone']);
+    $this->assertEquals($formatted['additional']['email'][0]['email'], $additionalContact['email']);
 
     $params = array(
       'version' => 3,
       'contact_id_a' => $contactId,
-      'contact_id_b' => $additionalContactId,
+      'contact_id_b' => $additionalContactId1,
       'relationship_type_id' => $this->_rtypeId,
     );
     $relation = civicrm_api('contact', 'get', $params);
     $this->assertAPISuccess($relation);
     $this->assertGreaterThan(0 , $relation['count'], 'Relationship result should greater than zero. In line '.__LINE__);
+
+    // duplicate case 1, won't add another contact
+    $formatted = CRM_Core_Payment_Backer::formatParams($json);
+    $this->_processor->processContribution($json, $contributionResult);
+    $params = array(
+      'version' => 3,
+      'last_name' => $formatted['additional']['last_name'],
+      'first_name' => $formatted['additional']['first_name'],
+    );
+    $result = civicrm_api('contact', 'get', $params);
+    $this->assertAPISuccess($result);
+    $this->assertEquals(1 , $result['count'], 'Additional contact count should be 1. In line '.__LINE__);
+
+    $params = array(
+      'version' => 3,
+      'last_name' => $formatted['additional']['last_name'],
+      'first_name' => $formatted['additional']['first_name'],
+    );
+    $result = civicrm_api('contact', 'get', $params);
+    $this->assertAPISuccess($result);
+    $this->assertGreaterThan(0 , $result['count'], 'Additional contact count should greater than zero. In line '.__LINE__);
+    $additionalContact = reset($result['values']);
+    $additionalContactId1 = $additionalContact['contact_id'];
+    $this->assertEquals($formatted['additional']['address'][0]['street_address'], $additionalContact['street_address']);
+    $this->assertEquals($formatted['additional']['phone'][0]['phone'], $additionalContact['phone']);
+    $this->assertEquals($formatted['additional']['email'][0]['email'], $additionalContact['email']);
+
+    // case 2, additional contact shouldn't be create again when missing email
+    $json = json_decode($this->_json[1], TRUE);
+    $json['transaction']['trade_no'] = CRM_Utils_String::createRandom(15);
+    $json['user']['id'] = mt_rand(100000, 999999);
+    $json['user']['email'] = 'admintest.main2@eaxmple.com';
+    $json['user']['name'] = '陳小刀';
+    $json['user']['cellphone'] = '+886900111222';
+    $json['recipient']['recipient_name'] = '陳小刀';
+    unset($json['recipient']['recipient_contact_email']);
+    $json['recipient']['recipient_cellphone'] = '0900111222';
+    $json = json_encode($json);
+    $formatted = CRM_Core_Payment_Backer::formatParams($json);
+
+    $contributionResult = NULL;
+    $this->_processor->processContribution($json, $contributionResult);
+    $createdContributionId = $contributionResult['contributionId'];
+    $this->assertNotEmpty($createdContributionId, "Contribution not created. In line " . __LINE__);
+    $contactId = CRM_Core_DAO::getFieldValue('CRM_Contribute_DAO_Contribution', $createdContributionId, 'contact_id');
+
+    $params = array(
+      'version' => 3,
+      'last_name' => $formatted['additional']['last_name'],
+      'first_name' => $formatted['additional']['first_name'],
+    );
+    $result = civicrm_api('contact', 'get', $params);
+    $this->assertAPISuccess($result);
+    $this->assertEquals(1 , $result['count'], 'Additional contact count should be only 1. In line '.__LINE__);
+    $additionalContact = reset($result['values']);
+    $additionalContactId2 = $additionalContact['contact_id'];
+    $this->assertEquals($additionalContactId2, $contactId, 'Additional contact should be same contact as previous after dedupe. In line '.__LINE__);
+    $blockValue = $formatted['additional']['address'][0];
+    $blockValue['contact_id'] = $contactId;
+    CRM_Core_BAO_Address::valueExists($blockValue);
+    $this->assertNotEmpty($blockValue['id'], "Additional address should be added to same contact. In line " . __LINE__);
+
+    // case 3, this should dupe original contact, no additional contact should be created
+    $json = json_decode($this->_json[1], TRUE);
+    $json['transaction']['trade_no'] = CRM_Utils_String::createRandom(15);
+    $json['user']['id'] = mt_rand(100000, 999999);
+    $json['user']['email'] = 'admintest.noadd@eaxmple.com';
+    $json['user']['name'] = '陳未增';
+    $json['user']['cellphone'] = '+886966777888';
+    $json['recipient']['recipient_name'] = '陳未增';
+    $json['recipient']['recipient_contact_email'] = 'admintest.noadd@eaxmple.com';
+    $json['recipient']['recipient_cellphone'] = '0977777888';
+    $json = json_encode($json);
+    $formatted = CRM_Core_Payment_Backer::formatParams($json);
+
+    $contributionResult = NULL;
+    $createdContributionId = $this->_processor->processContribution($json, $contributionResult);
+    $createdContributionId = $contributionResult['contributionId'];
+    $this->assertNotEmpty($createdContributionId, "Contribution not created. In line " . __LINE__);
+    $contactId = CRM_Core_DAO::getFieldValue('CRM_Contribute_DAO_Contribution', $createdContributionId, 'contact_id');
+
+    $blockValue = $formatted['additional']['address'][0];
+    $blockValue['contact_id'] = $contactId;
+    CRM_Core_BAO_Address::valueExists($blockValue);
+    $this->assertNotEmpty($blockValue['id'], "Additional address should be added to same contact. In line " . __LINE__);
+
+    $blockValue = $formatted['additional']['phone'][0];
+    $blockValue['contact_id'] = $contactId;
+    CRM_Core_BAO_Phone::valueExists($blockValue);
+    $this->assertNotEmpty($blockValue['id'], "Additional phone should be added to same contact. In line " . __LINE__);
   }
 
   function testBackerReceiptNew(){