i think bhav copy doesn't contain settlement price. it is the price at which futures positions are settled every day. currently i don't see settlement price in tick data, not even after 7 pm. this data is important to get to calculate settlement estimate for us. Liquid contracts are settled at closing price, but illiquids are settled at theoretical price.
below from nse website -
" The positions in the futures contracts for each member is marked-to-market to the daily settlement price of the futures contracts at the end of each trade day.
The profits/ losses are computed as the difference between the trade price or the previous day's settlement price, as the case may be, and the current day's settlement price. The CMs who have suffered a loss are required to pay the mark-to-market loss amount to NSE Clearing which is passed on to the members who have made a profit. This is known as daily mark-to-market settlement."
replacing actual LTP by theoretical settlement price (for illiquid contracts) vitiates the sanctity of 'trading' data. a separate column 'settlement_price' should be included in data (only in historical for it will be after market close only)
below from nse website -
" The positions in the futures contracts for each member is marked-to-market to the daily settlement price of the futures contracts at the end of each trade day.
The profits/ losses are computed as the difference between the trade price or the previous day's settlement price, as the case may be, and the current day's settlement price. The CMs who have suffered a loss are required to pay the mark-to-market loss amount to NSE Clearing which is passed on to the members who have made a profit. This is known as daily mark-to-market settlement."