Transfer of title: buyer takes no better title than seller unless owner precluded or mercantile agent validly sells in good faith. Where a non owner seller without the owner's authority sells goods, the buyer acquires no better title than the seller had, unless the owner is precluded by conduct from denying the seller's authority. If a mercantile agent, with the owner's consent, possesses the goods or a document of title, a sale made in the ordinary course of the agent's business is valid as if expressly authorised, provided the buyer acts in good faith and lacks notice of the agent's want of authority at the time of the contract.