Abby Bartine is a Litigation & Dispute Resolution partner in Mayer Brown’s Chicago office. Abby’s practice is focused on litigating individual and class claims arising under the Employee Retirement Income Security Act of 1974 (ERISA). She represents plan sponsors, benefit plans, and plan fiduciaries before the courts on a wide variety of ERISA claims involving defined contribution plans (401(k) and multi-employer plans), defined benefit plans, severance plans, top hat plans, and health plans. These lawsuits include allegations of excessive fees, imprudent investment management strategies, wrongfully denied benefits, and other claims relating to the administration of benefit plans and other fiduciary duties. Abby also represents clients in plan-related audits and investigations brought by the U.S. Department of Labor and Employee Benefits Security Administration.

In addition to her ERISA practice, Abby litigates cases across a range of substantive areas, such as post-closing disputes, professional liability cases, and mass torts and environmental claims, and has broad experience representing individuals and corporations in the course of internal investigations and compliance matters, as well as defending clients who are the subject of government investigations and enforcement actions.

Abby originally joined Mayer Brown in 2013 and rejoined the firm in 2019 after completing a two-year clerkship with the United States District Court for the Northern District of California. Abby graduated from the University of Iowa College of Law with highest distinction and was elected to the Order of the Coif. She was also a member and contributing editor of the Iowa Law Review. Prior to law school, Abby served as an aide in the United States Senate from 2008 to 2010.

Securities Investigations: Internal, Civil and Criminal


  • Represented a global defense company in two separate class actions challenging the administration and investments of its 401(k) plan with excess of $16 billion in assets. In both cases, achieved favorable settlements at the outset of trial after successfully narrowing the claims on summary judgment. 
  • Represents a global defense company in a nationwide class action challenging the administration of the company’s severance plan.
  • Representing a global oil and gas company in a nationwide putative class action against broad challenge to the administration of its retirement plan and selection of investment options.
  • Representing a large telecommunications company in a nationwide putative class action involving various alleged violations of ERISA in the calculation of actuarially equivalent pension benefits.
  • Represented an international bank in an individual claim for benefits and for equitable relief concerning determinations over eligibility for long-term disability benefits.


The University of Iowa College of Law, JD, with highest distinction
Order of the Coif; Contributing editor and student writer, Iowa Law Review

The University of Iowa, BA, with high distinction
Phi Beta Kappa


  • Illinois
  • California


  • US District Court for the Eastern District of Michigan
  • US District Court for the Northern District of California
  • US District Court for the Northern District of Illinois
  • US District Court for the Central District of Illinois