Chicago IL PTAB Trials Lawyers - Page 2 Chicago IL PTAB Trials Lawyers - Page 2. The best PTAB Trials Lawyers Chicago, IL. David M. Frischkorn Lawyer in Chicago, IL 300 South Wacker Drive Chicago, IL 60606 440 0 Sarah E. Fendrick, Ph.D. Lawyer in Chicago, IL 300 South Wacker Drive Chicago, IL 60606 654 0 Grantland G. Drutchas Lawyer in Chicago, IL 300 South Wacker Drive Chicago, IL 60606 333 0 Previous12Items 13-15 of 15