Judith Sindell (plaintiff) developed cancer allegedly as a result of her mother’s ingestion of the drug diethylstilbesterol (DES) during pregnancy. Several drug manufacturers produced DES based on the same formula, and Sindell did not know which manufacturer actually produced the specific drug that caused her harm. Sindell and a class of similarly affected women brought suit against Abbott Laboratories and other DES manufacturers (defendants). The trial court dismissed Sindell’s complaint because Sindell could not identify the manufacturer of the specific drug that caused her injuries. Sindell appealed.