diff --git a/stackalytics/processor/default_data_processor.py b/stackalytics/processor/default_data_processor.py
index bdd2a015d..29a260c1f 100644
--- a/stackalytics/processor/default_data_processor.py
+++ b/stackalytics/processor/default_data_processor.py
@@ -190,11 +190,8 @@ def _store_users(runtime_storage_inst, users):
     for user in users:
         stored_user = user_processor.load_user(runtime_storage_inst,
                                                user_id=user['user_id'])
-        if stored_user:
-            stored_user.update(user)
-            user = stored_user
-        user['static'] = True
-        user_processor.store_user(runtime_storage_inst, user)
+        updated_user = user_processor.update_user_profile(stored_user, user)
+        user_processor.store_user(runtime_storage_inst, updated_user)
 
 
 def _store_companies(runtime_storage_inst, companies):
diff --git a/stackalytics/processor/user_processor.py b/stackalytics/processor/user_processor.py
index 98236be8f..b7c13f4d8 100644
--- a/stackalytics/processor/user_processor.py
+++ b/stackalytics/processor/user_processor.py
@@ -12,6 +12,7 @@
 # implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+import copy
 
 from oslo_log import log as logging
 
@@ -88,3 +89,16 @@ def load_user(runtime_storage_inst, seq=None, user_id=None, email=None,
 def delete_user(runtime_storage_inst, user):
     LOG.debug('Delete user: %s', user)
     runtime_storage_inst.delete_by_key('user:%s' % user['seq'])
+
+
+def update_user_profile(stored_user, user):
+    # update stored_user with user and return it
+    if stored_user:
+        updated_user = copy.deepcopy(stored_user)
+        updated_user.update(user)
+        updated_user['emails'] = list(set(stored_user.get('emails', [])) |
+                                      set(user.get('emails', [])))
+    else:
+        updated_user = copy.deepcopy(user)
+    updated_user['static'] = True
+    return updated_user
diff --git a/tests/unit/test_user_processor.py b/tests/unit/test_user_processor.py
new file mode 100644
index 000000000..6d816f5ef
--- /dev/null
+++ b/tests/unit/test_user_processor.py
@@ -0,0 +1,89 @@
+# Copyright (c) 2015 Mirantis Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import testtools
+
+from stackalytics.processor import user_processor
+
+
+class TestUserProcessor(testtools.TestCase):
+    def setUp(self):
+        super(TestUserProcessor, self).setUp()
+
+    def test_update_user(self):
+        user = {
+            "launchpad_id": "user",
+            "companies": [
+                {
+                    "company_name": "Rackspace",
+                    "end_date": "2011-Nov-20"
+                },
+                {
+                    "company_name": "IBM",
+                    "end_date": None
+                }
+            ],
+            "user_name": "John Smith",
+            "emails": ["john@smith.com"]
+        }
+
+        stored_user = {
+            "launchpad_id": "user",
+            "companies": [
+                {
+                    "company_name": "Rackspace",
+                    "end_date": "2011-Nov-20"
+                },
+                {
+                    "company_name": "IBM",
+                    "end_date": None
+                }
+            ],
+            "user_name": "Johnny",
+            "emails": ["john@smith.com", "mapped_email@gmail.com"],
+            "static": True
+        }
+
+        updated_user = user_processor.update_user_profile(stored_user, user)
+
+        # merge emails from profile with those discovered by Stackalytics
+        self.assertEqual(set(stored_user['emails']),
+                         set(updated_user['emails']))
+        # name from the profile has higher priority over mined
+        self.assertEqual(user['user_name'], updated_user['user_name'])
+        # static flag must present
+        self.assertTrue(updated_user.get('static'))
+
+    def test_update_user_unknown_user(self):
+        user = {
+            "launchpad_id": "user",
+            "companies": [
+                {
+                    "company_name": "Rackspace",
+                    "end_date": "2011-Nov-20"
+                },
+                {
+                    "company_name": "IBM",
+                    "end_date": None
+                }
+            ],
+            "user_name": "John Smith",
+            "emails": ["john@smith.com"]
+        }
+
+        stored_user = None
+
+        updated_user = user_processor.update_user_profile(stored_user, user)
+        self.assertTrue(updated_user.get('static'))