Nathan focuses his practice on securities-related litigation, Financial Industry Regulatory Authority (FINRA), the United States Securities & Exchange Commission (SEC), and state securities commission regulatory investigations and disputes.

Nathan defends brokers, broker-dealers, and investment advisors in FINRA arbitrations, SEC actions, and FINRA enforcement actions. His practice also involves advising clients on how to navigate the complex financial services regulatory environment. Nathan has been listed as an Illinois Super Lawyer Rising Star.