Explain market share theory.
It was created by the CA Supreme Court in the case of Sindell v. Abbott Laboratories.
Courts using the theory generally require that the plaintiff prove that 1) all defendants are tortfeasors; 2) the allegedly harmful products are identical and share the same defective qualities; 3) the plaintiff is unable to identify which defendant causes her injury, through no fault of her own; and 4) the manufacturers of substantially all the defective products in the relevant area and during the relevant time are named as defendants.