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 Foursquare in Talks with Tech Firms for Strategic Investment as Ad Business Improves Social Network Expects Buy-In From as Many as 100 Advertisers for New Product , Published on August 29, 2013 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. Register Now Already a member? Log in.