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 CBS's Opening Bid for Upfront: 18% Price Hikes Rival Networks Ignore Fox Deals, Move to Maximize Sellers' Market By Brian Steinberg, Published on June 01, 2011 6 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.