Sean O'Shea is a highly experienced trial lawyer who focuses on complex commercial disputes, antitrust matters, and white collar defense and investigations. He represents corporations, financial institutions, investment funds, and senior executives in high‑stakes litigation and enforcement matters in federal and state courts nationwide.
O'Shea's practice includes both civil and criminal matters, with extensive experience litigating claims involving fraud, RICO, securities, and financial misconduct. He is widely regarded for his courtroom skill, particularly his effectiveness in cross‑examination, and has tried scores of cases to verdict across jury and bench trials, arbitrations, and administrative proceedings.
Lawdragon Honors
| Honor |
Year |
Practice |
| The 2026 Lawdragon 500 Leading Plaintiff Financial Lawyers |
2026 |
Financial Litigation, Antitrust |
| The 2026 Lawdragon 500 Global Leaders in Crisis Management |
2026 |
Investigations, White Collar, Litigation |
| Lawdragon Announces 2026 Hall of Fame Inductees |
2026 |
Trial Lawyer, White Collar |
| The 2026 Lawdragon 500 Leading Litigators in America |
2026 |
Trial Practice, White Collar, Investigations |
| The 2025 Lawdragon 500 Leading Global Litigators |
2025 |
International Litigation, Investigations |
| The 2025 Lawdragon 500 Leading Lawyers in America |
2025 |
Litigation, esp. White Collar |
| The 2025 Lawdragon 500 Leading Lawyers in America |
2024 |
Litigation, esp. White Collar |
| The 2025 Lawdragon 500 Leading Litigators in America |
2025 |
Trial Practice, White Collar, Investigations |
| The 2024 Lawdragon 500 Leading Global Litigators |
2024 |
International Litigation, Investigations |
| The 2024 Lawdragon Legends |
2024 |
|
| The 2024 Lawdragon 500 Leading Lawyers in America |
2024 |
Litigation, esp. White Collar |
| The 2024 Lawdragon 500 Leading Litigators in America |
2024 |
Trial Practice, White Collar, Investigations |
| Lawdragon 500 Leading Global Litigators |
2023 |
International Litigation, Investigations |
| The 2023 Lawdragon 500 Leading Lawyers in America |
2023 |
Litigation, esp. White Collar |
| Lawdragon 500 Leading Litigators in America |
2022 |
Trial Practice, White Collar, Investigations |
| The 2022 Lawdragon 500 Leading Lawyers in America |
2022 |
Litigation, esp. White Collar |
| The 2021 Lawdragon 500 Leading Lawyers in America |
2021 |
Litigation, esp. White Collar |
| The 2020 Lawdragon 500 Leading Lawyers in America |
2020 |
Litigation, esp. White Collar |
| The 2019 Lawdragon 500 Leading Lawyers in America |
2019 |
Litigation, esp. White Collar |
Referred to by a District Court judge as “one of the best trial lawyers I have ever seen,” O'Shea served for a decade as a federal prosecutor in the US Attorney’s Office for the Eastern District of New York, where he led the Business and Securities Fraud Section. In that role, he tried numerous jury cases and served as lead appellate counsel in complex criminal appeals. His work earned multiple commendations from the Department of Justice and federal law enforcement agencies.
O'Shea is consistently recognized by leading legal publications as one of the nation’s top trial and white collar lawyers. He is also committed to pro bono service and contributes to education, environmental conservation, and community‑based initiatives nationwide.
O'Shea earned his JD from Northwestern University Pritzker School of Law, where he was notes and comments editor of the Northwestern University Law Review. He has a BA from the University of Illinois.
