Hymowitz v. Eli Lilly and Co.
Citation and Court
Hymowitz v. Eli Lilly and Co., 539 N.E.2d 1069 (N.Y. 1989)
Facts
Plaintiffs were daughters of women who had taken DES (diethylstilbestrol), a synthetic estrogen prescribed to prevent miscarriages, which caused cancer and other injuries in their daughters. Because DES was a fungible drug manufactured by hundreds of companies over decades, plaintiffs could not identify which specific manufacturer had produced the DES their mothers took. All manufacturers had acted negligently, but the traditional requirement of proving which defendant caused the plaintiff’s harm made individual causation impossible to establish.
Issue
How may a plaintiff recover in tort when all defendants acted negligently but causation-in-fact cannot be proven against any particular defendant because the product is fungible?
Holding
The New York Court of Appeals adopted a market share liability theory, apportioning liability among defendant manufacturers according to their national market share of DES at the relevant time.
Rule / Doctrine
Under market share liability, when (1) all defendants manufactured an identical, fungible product, (2) all acted tortiously, (3) plaintiffs cannot through no fault of their own identify which defendant caused their specific harm, and (4) substantially all manufacturers are before the court, liability is apportioned by national market share. No individual defendant may exculpate itself by proving it did not make the specific DES pill that harmed any particular plaintiff — the focus shifts from individual causation to systemic industry responsibility.
Significance
Hymowitz is a landmark tort case expanding the market share liability doctrine beyond its California origins in Sindell v. Abbott Laboratories. The New York approach is notable for its categorical refusal to allow individual exculpation, distinguishing it from other jurisdictions. The case illustrates the tension between traditional tort causation requirements and the practical needs of plaintiffs injured by fungible products. It raises deep questions about whether tort law should serve purely corrective justice goals or whether enterprise liability principles are sometimes appropriate.