CDSL TPIN is a six-digit password that authorizes the broker to debit the selected stocks from the demat account of the holder having a demat account with CDSL. It is a crucial component of the stock trading process and is required for initiating a sell transaction on any Demat account. The CDSL TPIN is essentially an alternative to the Demat Power of Attorney (POA) . It is generated, managed, and stored by CDSL, and it is valid for 90 days after which it needs to be reset. The TPIN is issued by CDSL directly to customers, and there is also a provision to set a new TPIN, modify the existing TPIN, reset the TPIN facility entirely, and retrieve the TPIN through a specified link if you forgot the TPIN. The CDSL TPIN security mechanism enables investors to easily authorize any account-related action online, and it acts as an additional layer of security while making online Demat account transactions far safer and more secure. With a CDSL TPIN, clients can pre-authorize the sale of their stocks at the beginning of each trading day, eliminating the need to do it for every delivery sell order placed during the day. To sell an instrument by authorizing it through CDSL TPIN, one needs to follow the steps mentioned in the article.