You’ve read all of your free items this month. To register, get added benefits and unlimited access to articles, Become a Member. Already a Member? Sign in. Advertising Age Article Abstract Who's Going to Win Ad Tech's Coming 'Stack' Wars? Different Approaches to Putting the Ad Tech Humpty Dumpty Back Together Again By Adam Lehman, Published on March 28, 2012 1 Want more Access, Content & Connections? Upgrade to Membership. We are glad you are enjoying Advertising Age. To get uninterrupted access and additional benefits, become a member today. Become a Member Already a member? Log in.