Based on the criteria evidenced in this thread, certainly any company with scandalous pasts...
Republicans can never advertise, because they employ lies and deception throughout their organization. Actually, like banning religion, this may not be a bad thing;
Democrats, likewise;
Volkswagon can never advertise again, because of the corporate lies about vehicle emissions;
Well, all car companies, as they have all had scandals and recalls;
Banks for their previous illegal discrimination on lending;
Insurance companies for red-lining;
Law Enforcement wouldn't be able to provide public service advertisements, what with their abuses of the constitution in the past;
Military likewise;
Or, perhaps advertisements should be judged on the content of the specific advertisement being discussed, which happens to be how it is handled by the enforcement bodies responsible for monitoring advertising.