The hair relaxer MDL has become one of the largest active dockets in the federal system — 11,526 pending actions as of the Judicial Panel's May 1, 2026 statistical report, before Judge Mary M. Rowland in the Northern District of Illinois, with parallel proceedings running in Illinois state court, Philadelphia's coordinated mass tort program, Georgia, and New York. But the number that matters is not the case count. It is the single ruling all 11,526 cases are waiting on.
The procedural sequence tells you where the leverage sits. Judge Rowland held Science Day on January 8, with state court judges in attendance — a joint education session on the epidemiology connecting relaxer products to uterine, ovarian, and endometrial cancers, anchored by the 2022 Sister Study publication in the Journal of the National Cancer Institute. General-causation expert discovery for the 32-case bellwether pool closed March 2. Daubert motions on the causation experts came due April 1. Bellwether plaintiff depositions are substantially complete, and the parties have spent the spring fighting over whether corporate witnesses will sit for depositions at all, with defendants offering written stipulations on marketing, warnings, and labeling instead of live testimony. First trials are expected in 2027 — if the experts survive.
The Acetaminophen shadow
Every hair relaxer inventory in the country is priced against one precedent: the Acetaminophen MDL, where the court excluded plaintiffs' general-causation experts wholesale and the litigation collapsed without a bellwether ever reaching a jury. That is the downside scenario a causation Daubert ruling puts on the table, and it is why this gate functions as a binary repricing event. A ruling admitting plaintiffs' experts keeps the 2027 trial track alive, pressures defendants toward the settlement architecture already under construction, and makes late-filed cases worth acquiring. An exclusion order does to this docket what it did to Acetaminophen. There is not much middle.
The settlement scaffolding is notably ahead of the science ruling. Special Master Ellen K. Reisman, appointed in April 2025, has been coordinating valuation frameworks and mediating between plaintiffs' leadership and defendants across both the MDL and the state proceedings — synchronizing settlement structure with bellwether selection rather than waiting for a verdict. That is a court preparing for either outcome.
Two variables the spreadsheets miss
First, exposure proof. Unlike a pharmaceutical docket, there is no prescription record establishing product use. Usage history lives in purchase receipts, salon records, family testimony, photographs — consumer-behavior evidence that must be built case by case. That makes documentation quality, not diagnosis alone, the underwriting variable that separates a strong inventory from a padded one, and it is where deficiency rates will bite when a settlement matrix eventually demands proof.
Second, the Revlon channel. Claims against Revlon entities run through the confirmed bankruptcy plan, which imposed its own filing deadlines — enforced to the point of expunging claims in 2024 — and limits recovery to pre-petition insurance. An inventory heavy on Revlon-product users carries a structural haircut that has nothing to do with the merits, and cases naming Revlon defendants have been held under advisement in the MDL while the coordination questions resolve.
What firms should actually be doing
The window between now and the causation ruling is a document-completion window, not an acquisition window. Cases already signed should be closing record gaps — usage corroboration, complete oncology records, product identification tightened to brand and period — because bellwether-adjacent scrutiny is coming for the whole inventory, whichever way the ruling goes. Acquisition spend, meanwhile, is a bet on the ruling itself: claimant costs today reflect pre-Daubert uncertainty, and both the bull and bear cases resolve on one order from Judge Rowland's courtroom. Firms sizing that bet should read the docket, not the advertising market. Consumer-facing background on the litigation is at Lawsuit Informer, and the broader docket context is in the 2026 mass tort map.