Hi @Mitthi
We have explained it below here. In Pre-Market (from your screenshot), the data is similar - you can tap on the script and see the OHLC from the exchange.
More on this, how it works is below:
Any stocks or scrip available in your watchlist that have Extreme Opening will come with a purple or blue colour tag & text “O=H” & “O=L”. This signifies that the opening price of the stock for the day equals its highest or lowest price for the day, at that time.
If the stock has O=L tag i.e. open price equals low price, it means that the stock has moved only upside today and buyers are/were more aggressive than the sellers. Similarly, in case where the stock has O=H tag i.e. opening price equals high price, it means that the stock has moved only downside today and sellers are/were more aggressive than the buyers.
These tags will be updated twice; first at 9:08 AM basis the pre-market session. And second, when the market opens at 9:15 AM, depending upon the opening price at 9:15 AM. Additionally, at 9:15 AM, both tags of O=H and O=L will be visible for the same stock. This will prevail until price fluctuates due to further trading activity in those stocks.
Please note that these tags are updated in real time. For example, let’s say HDFC’s opening price at 9:15 AM was Rs. 1,600. Thereafter, the price stayed below this level till about 1:30 PM. From 9:15 AM to 1:30 PM the tag of O=H will be visible for HDFC. At 1:31 PM when HDFC price reaches Rs. 1601, the tag will disappear. Thus, the tags will be automatically updated in real time by the system, based on price movements.