Peter J. Brennan is a litigator.  Major multi-national corporations seek his counsel and representation on a wide variety of complex matters.  He has a nationwide and international practice.  He is a member of the firm’s Complex Commercial Litigation, Class Action and Consumer Law, Financial Services, Patent Litigation and Counseling, and State Enforcement and Regulation Practices.

Mr. Brennan is one of the few trial lawyers in the country to have actually tried a class action case that ultimately resulted in complete and total victory for his client in three different jurisdictions and eliminated the possibility of threatened suits in many other jurisdictions.  He has represented clients in courts in matters from the east coast to the west coast and from the Gulf Coast to the Great Lakes.  Those matters have involved significant patent litigation, major putative class actions, high-stakes commercial disputes and major insurance coverage disputes.

Mr. Brennan combines a passion for winning with a passionate team that conveys a sense of resolve to the decision-maker.  That can be particularly important in the close cases where his client’s opponent may be in a sympathetic circumstance.  He learned that early in his career when he had to deliver a closing argument after his then much more experienced colleague was hospitalized during a trial, leaving him to argue to the jury that a brain-damaged quadriplegic teenager should receive nothing.  He was able to do so by convincing the jury to follow the law as given to them by the judge even though their strong inclination was to favor the very sympathetic teenager.  That defense verdict was featured in the National Law Journal, particularly because the other side had declined a $7 million settlement offer (publicly disclosed).

Mr. Brennan’s passion is equally apparent in his appellate practice.  He has been honored to have argued before the highest courts of the States of Delaware, New York and Missouri.  Those cases were won by a combined vote tally of 17 to 1 and all overturned determinations at the trial level.

On the plaintiff side of the caption, he has been similarly successful.  For example, in a long-running action to recover a chemical company’s environmental remediation costs from various insurance companies he worked with a team of talented colleagues that resulted in a series of victories at the trial level and, three separate times, at the Second Circuit.  That case reached its culmination during a 2018 trial that resulted in a settlement in which the firm’s client was paid $120 million, a number that was publicly disclosed by the client as required by SEC regulations.

Of course, no victory is possible without a great team.  Mr. Brennan believes that Jenner & Block has been able to attract such talented lawyers in part because of the firm’s no. 1 rated pro bono program.  For each case that he has worked on, Mr. Brennan has been able to recruit brilliant yet down-to-earth colleagues who are able to identify and emphasize the key themes that are most likely to persuade judges and jurors.  For example, the team on one matter, which involved the auto industry, included a former automotive engineer and another associate who graduated first in his class from Harvard Law School where he served as president of the Harvard Law Review and subsequently clerked for Justice Kagan.  On another high-stakes matter that involved patent claims and alleged theft of intellectual property, he included in the team a first-generation American who also served on the Harvard Law Review, clerked for Chief Judge Garland, and led an extraordinary effort to defeat an injunction application that would have effectively destroyed a $20 million investment.  On a series of class actions, he worked with an associate who served as editor-in-chief of the Columbia Law Review and clerked for Justice Ginsburg.  She wrote a series of briefs that led to complete victory for our client.  All of those fine associates became partners in the firm.

The same theme holds true in the patent arena, where Mr. Brennan has worked with multiple attorneys who possess advanced engineering degrees, including up to the PhD level, yet are able to relate concepts effectively to the decision-makers, many of whom, of course, do not share a technical background.  That combination has led to great success.  For example, for one client, he defended it in a double-digit number of consecutive patent litigation matters, all of which have concluded with the client paying the patent holder absolutely nothing.

Although some of his matters have involved very large teams of people, Mr. Brennan makes sure to staff matters with the right number of colleagues and, if that just requires him working directly with an associate, as has been the case on multiple occasions, that is the way it is done.  Clients greatly appreciate that he makes sure that the client and the firm are completely aligned on the specific resources that will be brought to bear on a particular matter and, if some adjustment is needed, that will be discussed with the client before it is implemented.  His in-house experience earlier in his career has made him particularly sensitive to the needs of clients including making sure that neither the in-house counsel nor their internal business clients are unnecessarily surprised.

Earlier in his career, he served as head of litigation at what was then Sears, Roebuck and Co., where he supervised antitrust, consumer class action, ERISA, insurance coverage, patent, securities and other commercial and product liability litigation throughout the country.  During his tenure at Sears, he also took on additional assignments including supervising all the legal affairs for many of Sears’ businesses and advising on product safety and employment-related issues.

As an assistant corporation counsel for the City of Chicago, he gained extensive trial experience defending the City on a broad array of matters covering commercial, constitutional, employment, civil rights, tax, tort and other disputes.  For example, he defended the City during a 12-week trial against two of the most successful plaintiffs’ lawyers of that era that resulted in a successful settlement that those lawyers, contrary to established practice, insisted on keeping confidential.

After completing his judicial clerkship, he began his legal career as an associate in the litigation department of a large New York law firm.  During that time he worked on securities class action and commercial litigation at both the trial and appellate level.  His experience included working on two of the largest securities fraud class actions of that era as well as litigation arising out of a failed private placement transaction and a separate lawsuit involving a complex public bond financing, sale and leaseback transaction.


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    Business Litigation - 2012-2018