diff --git a/app/models/conversation.rb b/app/models/conversation.rb
index 3369bdb7d61..f45162f956c 100644
--- a/app/models/conversation.rb
+++ b/app/models/conversation.rb
@@ -427,15 +427,23 @@ class Conversation < ActiveRecord::Base
         (options[:only_users]).map(&:id)) if options[:only_users]
 
       skip_ids = options[:skip_users].try(:map, &:id) || [message.author_id]
-      skip_ids = [0] if skip_ids.empty?
       update_for_skips = options[:update_for_skips] != false
 
       # make sure this jumps to the top of the inbox and is marked as unread for anyone who's subscribed
-      cp_conditions = sanitize_sql([
-        "cp.conversation_id = ? AND cp.workflow_state <> 'unread' AND (cp.last_message_at IS NULL OR cp.subscribed) AND cp.user_id NOT IN (?)",
+      sql = "cp.conversation_id = ? AND cp.workflow_state <> 'unread' AND (cp.last_message_at IS NULL OR cp.subscribed)"
+      params = [
         self.id,
-        skip_ids
-      ])
+      ]
+      if skip_ids.present?
+        sql += " AND cp.user_id NOT IN (?)"
+        params << skip_ids
+      end
+      if options[:only_users]
+        sql += " AND cp.user_id IN (?)"
+        params << (options[:only_users]).map(&:id)
+      end
+      cp_conditions = sanitize_sql(params.unshift(sql))
+
       if %w{MySQL Mysql2}.include?(connection.adapter_name)
         connection.execute <<-SQL
           UPDATE users, conversation_participants cp
diff --git a/spec/models/conversation_spec.rb b/spec/models/conversation_spec.rb
index 992136ac14d..bbc5c95b5d0 100644
--- a/spec/models/conversation_spec.rb
+++ b/spec/models/conversation_spec.rb
@@ -283,6 +283,20 @@ describe Conversation do
         @unsubscribed_guy.conversations.unread.size.should eql 0
       end
 
+      it "should increment only for message participants" do
+        root_convo = Conversation.initiate([@sender, @recipient, @subscribed_guy], false)
+        root_convo.add_message(@sender, 'test')
+
+        @subscribed_guy.conversations.first.update_attribute(:workflow_state, "read")
+        @subscribed_guy.reload.unread_conversations_count.should eql 0
+        @subscribed_guy.conversations.unread.size.should eql 0
+
+        root_convo.add_message(@sender, 'test2', :only_users => [@recipient])
+
+        @subscribed_guy.reload.unread_conversations_count.should eql 0
+        @subscribed_guy.conversations.unread.size.should eql 0
+      end
+
       it "should decrement when deleting an unread conversation" do
         root_convo = Conversation.initiate([@sender, @unread_guy], false)
         root_convo.add_message(@sender, 'test')