## Facts

- Sandra Smith alleged she suffered injuries from in utero exposure to diethylstilbestrol (DES) ingested by her mother during pregnancy.
- DES was produced and distributed by numerous manufacturers; Smith could not identify which manufacturer made the specific DES her mother took.
- Smith sued multiple DES manufacturers alleging negligence and strict products liability.
- To address the inability to identify the producer, Smith sought to impose liability based on each defendant’s share of the DES market rather than proof of actual product identification.
- The trial court granted summary judgment for defendants on negligence, but allowed the strict liability claim to proceed under a market share theory.
- The appellate court affirmed and expanded the market share theory to apply to both negligence and strict liability.
- The Illinois Supreme Court granted review to decide whether Illinois should adopt market share liability in DES cases.

## Issues

1. Whether Illinois should adopt market share liability in DES cases to substitute proof of market participation for proof that a defendant manufactured the injury-causing product.
2. Whether such a theory may apply in negligence and/or strict products liability when the plaintiff cannot identify the specific manufacturer.

## Decision

- The Illinois Supreme Court rejected market share liability for DES cases.
- The court held that Illinois would not replace traditional causation-in-fact with a market-based probabilistic allocation of responsibility.
- The court reversed the appellate court’s judgment.
- The court directed entry of summary judgment for the defendant manufacturers because Smith could not identify the manufacturer of the DES that allegedly caused her injuries.

## Legal Principles

- A plaintiff in Illinois must prove causation in fact by establishing a causal connection between the defendant’s conduct or product and the plaintiff’s injury.
- Products liability and negligence claims generally require identification of the defendant as the manufacturer or supplier of the specific injury-causing product.
- Market share liability, which imposes liability without proof that a particular defendant made the product that caused the injury, is not recognized in Illinois.
- Broad policy decisions reallocating losses when specific causation cannot be shown are for the legislature rather than judicial modification of common-law causation rules.

## Conclusion

Illinois declined to adopt market share liability in DES litigation, holding that plaintiffs must identify the specific manufacturer responsible for the injury-causing product; inability to do so requires judgment for defendants in both negligence and strict liability claims.


Smith v. Eli Lilly & Co., 560 N.E.2d 324 (Ill. 1990)