Market Share Liability

Market share liability is a legal theory that lets an injured person recover damages from a group of manufacturers based on each company's share of the relevant product market, even when the plaintiff cannot prove which specific company made the product that caused the harm. Each defendant pays a portion of the damages roughly equal to its percentage of that market during the exposure period. The doctrine is the exception, not the rule. Most courts have declined to apply it in asbestos cases.

Origin

The doctrine was created by the California Supreme Court in Sindell v. Abbott Laboratories (1980), a case involving DES, a miscarriage drug that caused cancer in daughters of women who took it decades earlier. Because DES was a generic, chemically identical drug made by many companies, plaintiffs could not identify which manufacturer's pill their mother had taken, and the court fashioned market share liability to solve that proof problem.

Significance in Asbestos Context

For asbestos patients, market share liability sounds appealing because many people were exposed to dozens of products from different manufacturers decades ago and cannot recall brand names. In practice, however, most courts (including New York, Texas, and many others) have refused to extend the doctrine to asbestos cases. Their reasoning is that asbestos products were not fungible: different products (insulation, gaskets, joint compound, brake linings) contained different fiber types, in different concentrations, and posed different risks. Instead, asbestos plaintiffs usually must identify specific products through their own testimony, co-worker testimony, work records, or product identification witnesses, and pursue each manufacturer individually or through bankruptcy trusts.

Example Sentence

Her lawyers explained that because she worked around many different insulation brands at the shipyard, they would need product identification witnesses rather than rely on market share liability, which the state's courts have rejected in asbestos cases.

Related Terms

Product Identification, Joint and Several Liability, Substantial Factor Test, Alternative Liability, Asbestos Bankruptcy Trust, Causation

Notes

• Ask your attorney whether your state recognizes market share liability for asbestos at all. Most don't, so product identification evidence is usually essential.
• Start writing down every job site, employer, time period, and any product brand names, packaging colors, or supervisor names you can remember; share this list with your legal team early.
• Preserve old pay stubs, union records, W-2s, military service records (DD-214), and photographs from worksites. These often help identify which manufacturers' products were present.
• Ask family members and former co-workers if they will give statements; co-worker product identification is one of the strongest substitutes when market share liability is unavailable.