Zachary Ziliak

Managing Partner

A Rhodes Scholar with six college and graduate degrees, Zachary Ziliak worked for years in math, finance, and trading before becoming an attorney.  Through Ziliak Law, he provides clients in the investment management industry with top-tier, big-law know-how combined with hands-on experience in quantitative and automated trading.

Prior to law school, Zach completed graduate work in mathematics at the University of Oxford and an MBA with concentrations in finance and strategy from the University of Chicago.  He worked as a “quant” at UBS, a leading global investment bank, pricing exotic derivatives and forecasting volatility.  He then took over as head trader at Matlock Capital, designing and implementing an automated option-trading system.

At the Loyola University Chicago School of Law, Zach graduated first in his class, summa cum laude.  After clerking for Judge Janice Rogers Brown on the U.S. Court of Appeals for the D.C. Circuit, he joined the litigation practice at Mayer Brown, LLP.  Over six years at Mayer Brown, Zach managed discovery, worked with expert witnesses, argued before the Illinois Appellate Court, and drafted briefs for the Seventh and Eleventh Circuits, trial courts, and international and accounting arbitration hearings.  He wrote frequently on electronic discovery and is a member of the Seventh Circuit Electronic Discovery Pilot Program Committee.  Most importantly, Zach focused on applying his background in finance to the service of financial industry clients in a variety of capacities, including…

  • assisting a quantitative fund manager with an internal investigation and associated regulatory actions and litigation relating to an error in a computer trading model;
  • working with experts to design a methodology for estimating the impact of an error in a trading program;
  • advising fund managers on internal controls, compliance, and risk management, including drafting compliance procedures and error and escalation policies;
  • reviewing investment advisers’ client communications and drafting corresponding disclosures;
  • drafting briefs and managing discovery in a case involving disputed ownership of trading software;
  • analyzing client contracts and assisting with statistical studies as part of a leading custodial bank’s review of its foreign exchange trading practices; and
  • calculating damages and assisting with settlement negotiations in a class action involving callable CDs.

In May 2013, Zach left Mayer Brown to found Ziliak Law in order to focus yet further on servicing the trading companies and associated vendors that can benefit from his industry experience.  Through this purpose-built law firm, Zach is now able to broaden the range of services he offers to such companies.  In addition to the work he performed at Mayer Brown, Zach is available to assist with entity formation, contract negotiation, business planning, regulatory compliance, and many other issues companies in this industry encounter.


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Loyola University Chicago School of Law, JD

University of Chicago Booth School of Business, MBA

University of Oxford, ABD Mathematics

Indiana University, BS

Practice Areas



Professional Memberships

American Bar Association

Chicago Quantitative Alliance

Society of Quantitative Analysts


Board of Advisors: IIT Stuart Center for Strategic Finance

Expert Witness on Algorithmic Trading

Options Alliance


Seventh Circuit Electronic Discovery Pilot Program Committee

Small Business Advocacy Council

Traders Fulcrum


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141 W JACKSON BLVD | SUITE 4048 | CHICAGO, IL | 60604 | 312.462.3350
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