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Brent Wisner

Wisner Baum

R. Brent Wisner is managing partner of Wisner Baum San Francisco Bay Area office. Brent oversees all aspects of managing the firm and remains the firm’s lead trial attorney and directs the firm’s mass tort litigation and class actions. After obtaining two landmark verdicts against Monsanto, he has been showered with major awards and recognition. He is the youngest attorney in U.S. history to win a multi-billion-dollar jury verdict. Brent has achieved multiple verdicts totaling $2.427 billion, and negotiated mass tort settlements in excess of $1 billion.

Law360 named Mr. Wisner a “Titan of the Plaintiffs Bar” for, in part, his role as co-lead counsel in a complex trial that resulted in the first multi-million-dollar jury verdict against a brand-name drug-maker, GSK, holding it liable for injuries caused by a generic version of the drug Paxil. Also, because of this cutting-edge verdict, The National Law Journal recognized Brent and the firm as 2018 Elite Trial Lawyers and the first place winner in the category of Pharmaceutical Litigation.

In 2019, Brent and his colleagues filed lawsuits against the manufacturers of Zantac. The lawsuits were among the first of what will likely be many thousands. “Based on recent scientific findings, the levels of NDMA in Zantac are staggering,” says Wisner. “Considering how many people took Zantac in the U.S. since 1983, we are staring into the face of a public health crisis, and these defendants—in particular GSK and Pfizer—are to blame.”

The judge overseeing the Zantac multidistrict litigation (MDL No. 2924) appointed Brent to the Practices and Procedures Team to help establish the protocols and methodology for litigating tens of thousands of cases in the years to come.

Brent also serves as Co-lead Plaintiffs’ Liaison Counsel for the Ranitidine Product Cases, also known as the Ranitidine (Zantac) Judicial Council Coordinated Proceedings (JCCP 5150), California Superior Court for the County of Alameda. He is also Co-Chair of the Zantac Litigation Group for AAJ – American Association for Justice.

Brent Wisner served on the trial teams for the first three Monsanto Roundup trials. He served as co-lead trial counsel in two of the first three cases, delivering opening and closing arguments, and cross-examining many of Monsanto’s corporate witnesses.  The juries in the first three Roundup trials found that exposure to Monsanto’s Roundup weed killer caused the plaintiffs to develop non-Hodgkin lymphoma, awarding more than $2.424 billion in total damages. Brent also holds a judge-appointed leadership role as administrator and co-lead counsel for the Roundup Judicial Council Coordination Proceedings (JCCP), which consists of hundreds of Roundup cases consolidated before the California Superior Court for the County of Alameda (state court). He also serves as Liaison Counsel to MDL-2741 In Re: Roundup Products Liability Litigation for Roundup JCCP 4953 Alameda County.