diff --git a/app/controllers/projects/issues_controller.rb b/app/controllers/projects/issues_controller.rb
index 9d97c820f38..eef849d8209 100644
--- a/app/controllers/projects/issues_controller.rb
+++ b/app/controllers/projects/issues_controller.rb
@@ -76,7 +76,7 @@ class Projects::IssuesController < Projects::ApplicationController
   end
 
   def update
-    @issue.update_attributes(params[:issue].merge(author_id_of_changes: current_user.id))
+    @issue.update_attributes(params[:issue])
     @issue.reset_events_cache
 
     respond_to do |format|
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index 38e567f3b13..e6edceb1fbc 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -109,7 +109,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
     params[:merge_request].delete(:source_project_id)
     params[:merge_request].delete(:target_project_id)
 
-    if @merge_request.update_attributes(params[:merge_request].merge(author_id_of_changes: current_user.id))
+    if @merge_request.update_attributes(params[:merge_request])
       @merge_request.reset_events_cache
 
       respond_to do |format|
diff --git a/app/controllers/projects/milestones_controller.rb b/app/controllers/projects/milestones_controller.rb
index aea92a19f34..05237bbd2d2 100644
--- a/app/controllers/projects/milestones_controller.rb
+++ b/app/controllers/projects/milestones_controller.rb
@@ -38,7 +38,6 @@ class Projects::MilestonesController < Projects::ApplicationController
 
   def create
     @milestone = @project.milestones.new(params[:milestone])
-    @milestone.author_id_of_changes = current_user.id
 
     if @milestone.save
       redirect_to project_milestone_path(@project, @milestone)
@@ -48,7 +47,7 @@ class Projects::MilestonesController < Projects::ApplicationController
   end
 
   def update
-    @milestone.update_attributes(params[:milestone].merge(author_id_of_changes: current_user.id))
+    @milestone.update_attributes(params[:milestone])
 
     respond_to do |format|
       format.js
diff --git a/app/models/concerns/issuable.rb b/app/models/concerns/issuable.rb
index 75989888bfa..de167f8803a 100644
--- a/app/models/concerns/issuable.rb
+++ b/app/models/concerns/issuable.rb
@@ -37,8 +37,6 @@ module Issuable
              allow_nil: true,
              prefix: true
 
-    attr_accessor :author_id_of_changes
-
     attr_mentionable :title, :description
   end
 
diff --git a/app/models/issue.rb b/app/models/issue.rb
index a8dc6e5fd85..21040327741 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -30,8 +30,7 @@ class Issue < ActiveRecord::Base
   scope :of_user_team, ->(team) { where(project_id: team.project_ids, assignee_id: team.member_ids) }
 
   attr_accessible :title, :assignee_id, :position, :description,
-                  :milestone_id, :label_list, :author_id_of_changes,
-                  :state_event
+                  :milestone_id, :label_list, :state_event
 
   acts_as_taggable_on :labels
 
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 7c2648d8c7a..5c2b0656d40 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -38,7 +38,7 @@ class MergeRequest < ActiveRecord::Base
 
   delegate :commits, :diffs, :last_commit, :last_commit_short_sha, to: :merge_request_diff, prefix: nil
 
-  attr_accessible :title, :assignee_id, :source_project_id, :source_branch, :target_project_id, :target_branch, :milestone_id, :author_id_of_changes, :state_event, :description
+  attr_accessible :title, :assignee_id, :source_project_id, :source_branch, :target_project_id, :target_branch, :milestone_id, :state_event, :description
 
   attr_accessor :should_remove_source_branch
 
diff --git a/app/models/milestone.rb b/app/models/milestone.rb
index 1a73fa71e48..e16529a634c 100644
--- a/app/models/milestone.rb
+++ b/app/models/milestone.rb
@@ -16,8 +16,7 @@
 class Milestone < ActiveRecord::Base
   include InternalId
 
-  attr_accessible :title, :description, :due_date, :state_event, :author_id_of_changes
-  attr_accessor :author_id_of_changes
+  attr_accessible :title, :description, :due_date, :state_event
 
   belongs_to :project
   has_many :issues
@@ -89,6 +88,6 @@ class Milestone < ActiveRecord::Base
   end
 
   def author_id
-    author_id_of_changes
+    nil
   end
 end
diff --git a/app/observers/activity_observer.rb b/app/observers/activity_observer.rb
index d754ac8185a..c5420c275ae 100644
--- a/app/observers/activity_observer.rb
+++ b/app/observers/activity_observer.rb
@@ -2,8 +2,6 @@ class ActivityObserver < BaseObserver
   observe :issue, :note, :milestone
 
   def after_create(record)
-    event_author_id = record.author_id
-
     if record.kind_of?(Note)
       # Skip system notes, like status changes and cross-references.
       return true if record.system?
@@ -12,9 +10,7 @@ class ActivityObserver < BaseObserver
       return true if record.noteable_type.blank?
     end
 
-    if event_author_id
-      create_event(record, Event.determine_action(record))
-    end
+    create_event(record, Event.determine_action(record)) if current_user
   end
 
   def after_close(record, transition)
diff --git a/app/services/merge_requests/auto_merge_service.rb b/app/services/merge_requests/auto_merge_service.rb
index 9c9117f4687..e35c03275f2 100644
--- a/app/services/merge_requests/auto_merge_service.rb
+++ b/app/services/merge_requests/auto_merge_service.rb
@@ -9,11 +9,10 @@ module MergeRequests
       merge_request.lock
 
       if Gitlab::Satellite::MergeAction.new(current_user, merge_request).merge!(commit_message)
-        merge_request.author_id_of_changes = current_user.id
         merge_request.merge
 
         notification.merge_mr(merge_request, current_user)
-        create_merge_event(merge_request)
+        create_merge_event(merge_request, current_user)
         execute_project_hooks(merge_request)
 
         true
diff --git a/app/services/merge_requests/base_merge_service.rb b/app/services/merge_requests/base_merge_service.rb
index dbdb0063074..d0f777d50ec 100644
--- a/app/services/merge_requests/base_merge_service.rb
+++ b/app/services/merge_requests/base_merge_service.rb
@@ -7,13 +7,13 @@ module MergeRequests
       NotificationService.new
     end
 
-    def create_merge_event(merge_request)
+    def create_merge_event(merge_request, current_user)
       Event.create(
         project: merge_request.target_project,
         target_id: merge_request.id,
         target_type: merge_request.class.name,
         action: Event::MERGED,
-        author_id: merge_request.author_id_of_changes
+        author_id: current_user.id
       )
     end
 
diff --git a/app/services/merge_requests/merge_service.rb b/app/services/merge_requests/merge_service.rb
index 80487f661e0..680766140bd 100644
--- a/app/services/merge_requests/merge_service.rb
+++ b/app/services/merge_requests/merge_service.rb
@@ -7,11 +7,10 @@ module MergeRequests
   # to target branch
   class MergeService < BaseMergeService
     def execute(merge_request, current_user, commit_message)
-      merge_request.author_id_of_changes = current_user.id
       merge_request.merge
 
       notification.merge_mr(merge_request, current_user)
-      create_merge_event(merge_request)
+      create_merge_event(merge_request, current_user)
       execute_project_hooks(merge_request)
 
       true