Fundamental Glossary / Indian Stock Market-Specific Fundamentals
Block Deals
Large trades executed in a separate window so that a single negotiated transaction does not disrupt the normal order book.
Formula
Under the SEBI framework the exchanges run a morning window, with the previous close as the reference, and an afternoon window, with a VWAP reference. Orders must be within plus or minus 1% of that reference. The minimum order size is Rs 10 crore, and the trade must result in delivery. The exchange disseminates the deals the same day.
What it means
A block deal is designed for size. The price is kept close to the reference so the rest of the market is not surprised by a print far away from the last trade.
Because it is delivery-based, it changes ownership. It is a register event as well as a tape event.
How to read it
The useful question is who sold and who bought, not the fact that a block window exists. A promoter trim and an institutional switch have different fundamental meanings.
What to watch
The minimum size and the windows are regulatory facts and can be amended. Check the current exchange circular before you treat a number in an old article as today's rule. This note follows the SEBI trading review and the NSE block-deal description of the Rs 10 crore minimum.
This note explains the term. It is not a research recommendation, a target price, or a comment on any security. Ratios and regulatory thresholds change; use the latest filing or circular for a live figure.