Nemo dat quid non habet
The word Nemo dat quid non habet no one gives what they don't have. It is also called as memo dat rule which state that the purchase of position from someone who has don't hold a ownership right to the position it also denies the purchaser any ownership title.
under section 27 when the seller himself is the owner of the goods which he sailed for he is number deviation to dispose of the goods conveys a good title in the goods to the buyer difficulty arises when the seller is neither himself the owner nor he hold any of such authority from the owner to sell the goods.
The concept Nemo dat quid non habet is equivalent to Civil law which defines the the Memo plus juris ad allium transferee potest quam ipse Haber rule which means one cannot transfer to another more right then they have.
Section 27 subject to provision of this act and of any other law for time being in force where goods are sold by one person who is not the owner thereof and who does not sell them under the authority or with the consent of the owner the buyer acquires no better title to the goods than the seller had.
Exception to the rule
There are various exception to the rule have been mentioned in this act and in Contract Act and in those exceptional situation the seller of the goods may not be having a good title. The seller of the goods may not be having good title to the good yet the buyer of them gets a good tittle
1.Sale under the implied authority of the owner of transfer of title by estoppel
2. Sale by mercantile agent
3. Sale by a person in possession under voidable contract
4. Sale by one joint owner
5. Sale by the buyer in the possession of the goods before in which has passed to buyer
6. Sale buy the finder of goods
7. Resale of goods by an unpaid seller after he has exercise the right of lien are stoppage of transit