1.0 Parties Responsible for a Defective Product after being sold.

Anyone linked to the distribution of a product can be perceived as the responsible party. This includes manufacturers, wholesalers, retail outlets, and even someone in charge of assembling or installing the product. For strict liability to apply, the exchange of a product must occur somewhere in the professional supply chain. For example, someone who sells a product on the secondary market (e.g., garage sale) cannot be held accountable for product liability.

2.0 Defendants in Product Liability Cases Generally, the claimant in a product liability case should identify all parties in the product's chain of distribution that may have caused their injuries. The following outlines the parties involved in the chain of distribution that may be liable for a defective or faulty product. In some cases, there may be more than one potential defendant in each category. 2.1 Manufacturer (engineer) Manufacturing takes place at the beginning of a product's chain of distribution. The manufacturer of a faulty product may range from a large, multinational corporation to a person working out of a garage.
When a defective product is part of a larger item, the injured consumer may have a claim against both the manufacturer of the faulty part and the maker of the product itself. For instance, if a consumer was injured in a motor vehicle containing an exploding battery, they could potentially file a claim against the automaker and the battery manufacturer.
When identifying a defendant in a product liability case, it's important to include additional parties involved in the design, manufacturing or marketing of a product who may be associated with the defect. For instance, product liability claims stemming from a manufacturing defect may cite quality control engineers as a liable party. Similarly, a lawsuit may name a design consultant as the defendant if a faulty product resulted from a design defect. Product liability claims involving a failure to warn may name technical experts who wrote instructions or warning labels for the product.

2.2 Retailer
Although retailers are typically not involved in the manufacturing of products, they may still be held accountable for selling a faulty item. In product liability lawsuits, the injured consumer is not required to pick one defendant over another. Any part in the product's chain of distribution can be named as the defendant in a defective product lawsuit.
Injured consumers should remember that when bringing a product liability claim against a retailer, they do not have to be the buyer of the product. For instance, if an individual became ill after taking improperly manufactured aspirin supplied by a friend or co-worker, they are not prevented from filing a product liability claim against the retailer simply because they did not personally purchase the item.
Likewise, the injured party does not have to be the user of the defective product and may be able to recover compensation for used products depending on the nature of the defect, product type and applicable state product liability laws. 2.3 Wholesaler or Distributor
Wholesalers, distributors and suppliers are the "middlemen" in between the manufacturer and the retailer. These parties are part of a product's chain of distribution and therefore may be found legally liable in a defective product lawsuit.
Ref: http://www.forthepeople.com/parties-responsible-for-a-defective-product--1-1588.html
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