Ms. Sonneborn is a partner in the Labor & Employment Department of Seyfarth Shaw LLP. She actively advises clients in the health care, construction, print media, hotel, gaming, manufacturing, transportation, and energy industries. Ms. Sonneborn previously was named one of the National Law Journal’s 40 Under 40 Rising Stars in Chicago. Ms. Sonneborn also serves as vice-chair of the Chicago office’s Labor & Employment Department.
Ms. Sonneborn has considerable experience in the area of Employee Retirement Income Security Act of 1974 (ERISA) litigation. Ms. Sonneborn is co-chair of the Firm’s ERISA & Employee Benefits Litigation practice group. Her ERISA and employee benefits litigation experience includes defense of single plaintiff claims for benefits, breach of fiduciary duty claims, cash balance plan claims, breach of contract claims, and ERISA Section 510 employment discrimination claims. Ms. Sonneborn devotes a considerable amount of her practice to litigation of class-action and multi-plaintiff claims. She also frequently advises clients regarding handling of claims brought under benefit plan claims procedures. Ms. Sonneborn has handled hundreds of single plaintiff cases brought in federal court under ERISA. She also frequently speaks on ERISA litigation issues and serves as a chapter editor for the American Bar Association book on Employee Benefits.
Ms. Sonneborn is also particularly well-versed in the field of labor relations law, with a particular focus on advising clients in the health care industry. Within this arena, she has represented clients in unfair labor practice proceedings, contractual arbitrations, representation proceedings, and Section 301 litigation. She also has experience advising clients during union organizing campaigns. In addition, she provides clients with day-to-day labor relations advice on a wide spectrum of topics, including independent contractor issues, neutrality agreements, and corporate campaigns.
Ms. Sonneborn has substantial experience with non-union employment issues as well. She has represented clients in litigation under the Fair Labor Standards Act, Title VII of the Civil Rights Act, the Americans with Disabilities Act, the Family and Medical Leave Act, the WARN Act, the Illinois Human Rights Act, the Illinois Minimum Wage Act, the Minnesota Human Rights Act, and Michigan’s Elliott-Larsen Civil Rights Act. Ms. Sonneborn also counsels various clients on day-to-day employment law matters and assists clients with revisions to employee policies and employment applications.
Ms. Sonneborn leads various training courses with Seyfarth Shaw at Work®, including anti-harassment training and positive employee relations training. She also serves as an adjunct faculty member in the Legal Writing Department at Chicago-Kent IIT College of Law.
