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California Supreme Court Considers Component Parts Doctrine

Last week, the California Supreme Court granted review of Ramos v. Brenntag Specialties, Inc. to resolve a split in the Second Appellate District regarding the application of California’s component parts doctrine.  The component parts doctrine stands for the proposition that a company that manufactures component parts cannot be sued under a strict liability theory for a finished product that incorporates its component.

The rationale for not imposing liability on suppliers of product components is a matter of public policy:  such suppliers generally do not participate in developing their component products into finished products for consumers.  Imposing liability on these suppliers would impose a burden on them to closely examine buyer-manufacturers’ processes and final end products in order to ameliorate the suppliers’ potential legal exposure, despite the fact that buyer-manufacturers are in the best position to ensure product  safety.

In Ramos, the plaintiff brought a suit for negligence, negligence per se, strict liability, and loss of consortium, alleging that his exposure to dust from defendants’ products, including metal, plaster, sand, limestone and marble, during his employment at a metal foundry caused his pulmonary fibrosis.  The defendants moved to dismiss on the basis of the Component Parts Doctrine, and the trial court sustained their motion to dismiss without leave to amend.   The Second District reversed the trial court’s rulings on all claims except the negligence per se claim.

After a thorough examination of precedent on the subject, the Second District stated that “the component parts doctrine does not shield a product supplier from liability when a party alleges that he suffered direct injury from using the supplier’s product as the supplier specifically intended.”  The court explained that Ramos’ complaint alleged a direct injury from the intended use of the defendants’ products, and not from a finished product, manufacturing process into which the products were integrated, or an apparatus built to the employer’s specifications.  Further, Ramos’ complaint did not allege that he suffered injuries from a defective “integrated product” that incorporated the defendants’ products, but rather that he suffered injuries from the products themselves.

In reaching its conclusion in Ramos, the Second District relied heavily on the Artiglio case, decided in 1998, rather than on the Maxton decision that the Second District reached only two years before Ramos.  In Maxton v. Western States Metals, the Second District applied the component parts doctrine to manufacturers and suppliers of raw materials in a case that was factually similar to Ramos.  Plaintiff Maxton was a laborer for a manufacturing company that utilized metal products who alleged that his exposure to fumes from defendants’ raw materials caused his pulmonary fibrosis.

Applying the four factors from Artiglio, the Maxton court found that the component parts doctrine barred claims of negligence and strict liability against the defendants because their products were not inherently dangerous, they sold them to a sophisticated buyer, their products were substantially changed during the manufacturing process, and the defendants played no role in developing or designing the employer’s end products.  The Maxton court also focused on public policy in reaching its conclusion.

At this juncture, it is unclear whether Maxton and its application of the component parts doctrine will survive.

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Daniel J. Herling

Member / Co-chair, Product Liability Practice

Daniel J. Herling is a highly regarded product liability defense attorney at Mintz. He handles litigation and class actions involving consumer products, leveraging his deep knowledge of California's consumer protection regulations and laws.