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 Patent Trolls Are a Big Headache for Ad Agencies, Too Nefarious Lawsuits Estimated to Cost Ad Agencies $10 Million a Year By Nancy Hill, Published on March 11, 2013 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. Register Now Already a member? Log in.