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 WPP Media Agency Group to Offer Flexible Alternative to Xaxis Move Comes as More Clients Threaten to Bring Programmatic Buying In-House By Alexandra Bruell, Published on August 08, 2014 0 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.