Nemo dat quod non habet, literally means “no one gives what he doesn’t have”. This is a legal rule, sometimes called the nemo dat rule, which states that the purchase of a possession from someone who has no ownership right to it also denies the purchaser any ownership title.
It is equivalent to the civil “Nemo plus iuris ad alium transferre potest quam ipse habet” rule, which means “one cannot transfer more rights than he has”.
The rule usually stays valid even if the purchaser does not know that the seller has no right to claim ownership of the object of the transaction; however, in many cases, more than one innocent party is involved, making judgment difficult for courts and leading to numerous exceptions to the general rule that aim to give a degree of protection to bona fide purchasers and original owners.
The possession of the good of title will be with the original owner.
The original owner can obtain protection against the former owner through the doctrine of estoppel (see also, s 21(1) of the Sale of Goods Act 1979 ‘…unless the owner of the goods is by his conduct precluded from denying the seller’s authority to sell). Methods of the estoppel can be by words, by conduct, or by negligence.