Critical Mass: 11th Circuit Questions Zantac Judge’s Expert Ruling, Circuit Split Emerges Over Class Certification in Auto Insurance Cases
In the latest edition of Law.com’s Critical Mass newsletter (October 15, 2025), reporter Amanda Bronstad dissects two seismic shifts in mass tort and class action litigation: a federal appeals court’s pointed scrutiny of a landmark Zantac expert exclusion ruling that derailed thousands of cancer claims, and a fresh circuit split cementing divergent paths on certifying auto insurance valuation classes against giants like State Farm and Progressive. These developments, drawn from oral arguments and a pivotal Sixth Circuit affirmance, signal escalating battles over scientific gatekeeping and commonality in consumer suits—potentially teeing up Supreme Court review amid a docket clogged with 70,000+ Zantac filings and surging insurance challenges. Bronstad’s dispatch (a brisk 5-minute read) spotlights the high-stakes tension between judicial rigor and access to justice, with defense wins under fire.
11th Circuit Grills Defense on Zantac Daubert Ruling: ‘Was She a Little Too Thorough?’
The U.S. Court of Appeals for the Eleventh Circuit turned up the heat on October 10, 2025, during oral arguments in an interlocutory appeal challenging U.S. District Judge Robin L. Rosenberg’s infamous 341-page December 2022 order excluding plaintiffs’ general causation experts in the Zantac multidistrict litigation (MDL). Rosenberg’s ruling—hailed by pharma defendants as a Daubert triumph but lambasted by plaintiffs as overreach—effectively dismissed over 5,000 bellwether cases in the Southern District of Florida, arguing the experts’ methodologies linking ranitidine (Zantac’s active ingredient) to cancer were unreliable “analytical leaps” unsupported by peer-reviewed science. With 70,000+ suits consolidated under Judge Denise Cote in the Southern District of New York facing similar scrutiny, the appeal (In re Zantac (Ranitidine) Products Liability Litigation, No. 23-10726) could ripple nationwide.
A three-judge panel—featuring Circuit Judge Adalberto Jose Jordan, joined by Judges Jill A. Pryor and Elizabeth Warren—probed defense counsel Joseph Petrosinelli (Gibson Dunn) on whether Rosenberg veered into impermissible fact-finding. Jordan quipped, “Was she a little too thorough?” during a 45-minute grilling, suggesting the district judge preempted cross-examination by dissecting expert reports herself: “The experts could have faced inquiries during cross examination.” Plaintiffs’ attorney James Streble (DiCello Levitt) countered that Rosenberg’s “encyclopedic” analysis blurred lines between gatekeeper and trier-of-fact, violating Daubert v. Merrell Dow Pharmaceuticals standards. The panel also questioned the timing: Rosenberg’s order predated key FDA and EMA data on NDMA degradation, potentially rendering it moot.
Implications? A reversal could revive Florida bellwethers, pressuring global defendants like GSK, Pfizer, Sanofi, and Boehringer Ingelheim (facing $45 billion in potential exposure). Bronstad notes this aligns with wins elsewhere: The Delaware Supreme Court greenlit 10 plaintiff experts in September 2024, while a California state court rejected exclusions last month. No ruling timeline, but expect fireworks—plaintiffs decry “judicial activism” favoring Big Pharma, while defendants tout it as science over speculation.
Sixth Circuit Bucks Trend, Affirms Massive State Farm Class—Sparking Circuit Split on Valuation Claims
In a Thursday bombshell, the U.S. Court of Appeals for the Sixth Circuit affirmed class certification for 90,000 Tennessee policyholders suing State Farm over alleged underpayment of total-loss vehicle claims, creating a stark circuit split with four peers who’ve torpedoed similar suits against Progressive this year. The 2-1 decision (Bridgeforth v. State Farm Mutual Automobile Insurance Co., No. 24-5123) upheld U.S. District Judge Sheryl H. Lipman’s Western District of Tennessee order, ruling plaintiffs met Rule 23’s predominance via a “uniform methodology” for valuing wrecked cars—contrasting actual cash value (ACV) against inflated “comparable vehicle” adjustments.
The panel, led by Judge John K. Bush with Judge Amul R. Thapar concurring, dismissed State Farm’s variance arguments: “The district court did not abuse its discretion” in finding common questions (e.g., systematic deductions) outweighed individualized proofs. Dissenting Judge Danny C. Reeves warned of “fail-safe” classes, echoing rejections in the Third (In re Progressive Casualty Insurance Co. Auto Insurance Litigation, 2025), Fourth, Seventh, and Ninth Circuits, where judges decertified for lacking ascertainability and predominance amid state-specific regs.
Bronstad highlights the stakes: These “total loss” suits—alleging insurers shave 10-20% off payouts via proprietary software—have ballooned post-Comcast v. Behrend (2013), with $1 billion+ in play. The split could force SCOTUS intervention, especially as the Sixth’s pro-cert stance emboldens filings in friendlier venues like Memphis. Defense groups like the Insurance Information Institute hail the outlier rulings as safeguards against “overreach,” but plaintiffs’ firms see a green light for nationwide discovery.
Other Hot Takes from Critical Mass
Bronstad rounds out with quick hits: A Florida federal judge denied GSK’s bid to toss Zantac claims despite expert woes; anti-moonlighting suits proliferate against tech firms; and wage transparency challenges hit HR platforms. Her lens? These threads weave a tapestry of evolving evidentiary hurdles in an era of AI-driven valuations and degraded drug probes.
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