MWPL Explained — Understand the difference between Raw OI and Future Equivalent (delta-adjusted) OI in MWPL calculations

There are many things we need to know while trading futures and options. However, it becomes difficult to trade when you are unaware of future events, news, or other market developments, as these factors can directly impact your positions and trading strategy.

One key concept, MWPL (Market-Wide Position Limit), becomes especially important when a stock experiences significant price movement and also has a low free float. This is not just about price fluctuations — it also affects hedging positions, margin requirements, and, most importantly, trading volume and trading restrictions.

Several things can happen when a stock comes under the MWPL limit.

What is the meaning of MWPL?

Market-wide position limit (MWPL) is simply a concept in F&O or derivative trading that prevents clients from becoming overexposed by taking excessively large positions. In this case, each company has a maximum position limit — MWPL — set by SEBI. Under the current framework (effective since October 2025), MWPL is calculated as the lower of 15% of the stock’s free-float market capitalization or 65 times its average daily delivery value (ADDV) in the cash market, subject to a floor of 10% of free float. This replaced the earlier rule, which was based purely on free float. The idea is to tie the derivatives limit not just to how many shares are available, but to how liquid the stock actually is in day-to-day cash trading.

If the total open interest exceeds the prescribed limit, SEBI imposes a restriction when the MWPL reaches 95%. Once the MWPL reaches this 95% level, the stock enters the F&O ban period. In that case, no one is allowed to take fresh positions in the F&O segment, although existing positions can generally be squared off.

This restriction reduces the overall trading volume in the derivatives contract, which can also affect the premiums of the stock’s options.

Role of Free-Float Market Capitalization in F&O Position Limits

It is very important to understand why certain companies frequently appear on the daily F&O ban list, while others do not. You can identify these companies by tracking the F&O ban list. One of the key reasons is the company’s free float and delivery liquidity. Free-float market capitalization refers to the portion of a company’s shares that is freely available for trading in the market. Since MWPL is now the lower of 15% of free float or 65× ADDV, a stock with a low free float — or one with thin cash-market delivery volumes relative to its derivatives activity — hits its position limit faster. For example, if a company has only 10% of its total shares available as free float, or sees low daily delivery volumes even with heavy F&O trading, there’s a higher chance it enters the F&O ban period.

On the other hand, a stock with a free float of around 40–50% and healthy average daily delivery volumes has a larger MWPL cushion, so it’s less likely to enter the ban period under normal market conditions. However, this does not mean that it cannot enter the ban period. A major event or situation that attracts significant investor attention and leads to a substantial increase in trading activity can still cause the stock to approach its F&O position limit.

MWPL Limit: Raw Open Interest vs. Delta-Adjusted Open Interest

There is often a difference between the MWPL limit calculated using raw open interest and the MWPL limit calculated using futures-equivalent or delta-adjusted open interest. This can create confusion among traders about which MWPL figure is the correct one.

Sometimes, you may see the MWPL crossing 120%, 130%, or even 150%, while the stock still does not enter the F&O ban period. Conversely, the MWPL may remain below 95%, and the stock may still be in the ban period. This can even happen on the same day. Therefore, it is important to understand the positive and negative aspects of both MWPL and the F&O ban to understand why such situations occur.

Let’s understand with an example:

As you can see, the raw MWPL open interest for each strike price is the same. When we add the futures position to this, they contribute different quantities. However, when we adjust the open interest using delta, it makes a significant difference.

For example, if we take the 3700 strike price, we can see that five lots of options and one lot of futures account for nearly 900 quantities. At the same time, after applying the delta adjustment, it accounts for only around 510 quantities.

Here, let’s say we have an MWPL of Kaynes Technology, which is 40 lakh shares. Now, if someone takes a large number of positions in options and futures, the total position might be higher than 40 lakh shares because the quantity is calculated without delta adjustment.

However, when we adjust the position using delta, the quantity can be drastically lower, bringing it to around or below 95%. If the delta-adjusted MWPL goes above 95%, then the stock would be considered to be approaching the F&O ban threshold.

So, this is the ultimate way to understand the difference between raw open interest and delta-adjusted MWPL, and how the MWPL is calculated after adjusting the positions for delta.

This is the main reason why we sometimes see MWPL crossing 150%. The figure above 100% is based on the raw OI considered for MWPL, not the delta-adjusted MWPL.

Live MWPL Data Tracking

When we look at the F&O ban list, one of the most important things to know is whether a stock is likely to come out of the ban on the next trading day.

To determine this, we need to track how much open interest (OI) has been created in both futures and options. We can easily monitor the change in futures OI, but calculating the exact options OI is much more difficult, because we need the open interest for every individual option strike and expiry, and then we must convert all of those positions into their futures equivalent. This is a complex and time-consuming process.

Moreover, the exchanges do not provide real-time Futures Equivalent OI or live MWPL utilization data. Instead, they publish official data files at the end of each trading day. We process these files and update the information in our F&O Ban List, which provides the most reliable way to track the latest MWPL status.

This is important because even if MWPL utilization falls below 80% during the trading session, the stock does not immediately come out of the F&O ban. The exchanges review the official end-of-day data, and if the utilization is below the required threshold, the stock is removed from the ban list on the following trading day. That is why we update the F&O Ban List daily — to let you know whether a stock is expected to remain in the ban or come out of it.