If a product liability action is commenced against a seller, and it is alleged that a product was defectively designed, contained defectively manufactured parts, had insufficient safety guards, or had inaccurate or insufficient warning; that such condition existed when the product left the control of the manufacturer; that the seller has not substantially altered the product; and that the defective condition or lack of safety guards or adequate warnings caused the injury or damage complained of; the manufacturer from whom the product was acquired by the seller must be required to assume the cost of defense of the action, and any liability that may be imposed on the seller. The obligation to assume the seller’s cost of defense should also extend to an action in which the manufacturer and seller are ultimately found not liable.