Indian financial media quotes open interest and put-call ratios constantly, usually without explaining either. Both are real data with genuine information in them, and both are routinely over-interpreted. This lesson covers what they measure and where the interpretation stops being defensible.
What open interest is
That distinction is what makes it useful: rising open interest means new money is entering the position, not just existing holders passing contracts between themselves.
The four combinations
| Price | Open interest | Interpretation |
|---|---|---|
| Rising | Rising | Long buildup. New buyers entering with conviction. The most genuinely bullish combination. |
| Rising | Falling | Short covering. Shorts closing out, which lifts price. A technical bounce, not new demand — it tends to fade once covering finishes. |
| Falling | Rising | Short buildup. New sellers entering. Genuinely bearish. |
| Falling | Falling | Long unwinding. Existing longs exiting. Weak hands leaving rather than new selling pressure. |
Put-call ratio
- High PCR (>1.3)
- Heavy put positioning — usually read as excessive fear, so contrarian bullish
- Low PCR (<0.7)
- Heavy call positioning — usually read as complacency, so contrarian bearish
Example: PCR is a sentiment gauge used contrarily: extremes suggest the crowd is heavily positioned one way, and crowded positions unwind violently. Like all sentiment measures, it identifies conditions, not timing.
Support and resistance from the option chain
One genuinely useful application. The strike with the highest call open interest often acts as resistance, and the strike with the highest put open interest often acts as support. The mechanism is real: option writers at those strikes hedge their exposure, and that hedging creates actual buying and selling pressure around those levels.
Max pain, honestly
"Max pain" is the strike at which the largest rupee value of options would expire worthless — the price causing maximum aggregate loss to option buyers. The theory says price gravitates there by expiry.
Where to get this data
- NSE option chain — published live and free. Strike-wise open interest, change in open interest, volume and implied volatility.
- Daily participant-wise OI — NSE publishes how FIIs, DIIs, proprietary desks and clients are positioned in index and stock futures and options. The client category is everybody who is not one of the other three, not retail alone. Genuinely informative and almost nobody reads it.
- India VIX — expected 30-day volatility, which is what options are actually pricing.
Reading the derivatives data
3 questions. Answers are revealed once you submit all of them.
1.A stock rises 6% while open interest in its futures falls 22%. What is most likely happening?
2.Why is a high put-call ratio not straightforwardly bearish positioning?
3.How should max pain be treated?
Circus mein kitne tickets bike, woh volume hai. Kitne log abhi bhi seat pe baithe hain, woh open interest hai. Dono alag baat hai. Bhaav badhe aur OI bhi badhe — matlab naye log andar aa rahe hain. Bhaav badhe par OI gire — matlab purane log nikal rahe hain.
- Open interest counts live positions; volume counts transactions. Rising OI means new money.
- Price up with OI up is a long buildup; price up with OI down is short covering, which fades.
- PCR does not record intent — high put OI can be bullish institutional positioning.
- The highest call and put OI strikes often act as resistance and support, through real hedging flows.
- Max pain is a weak tendency, not a forecast — and you can read all of this without trading derivatives.
Mark it done to track your progress through the curriculum.
Common questions
Short, direct answers to what people ask about this topic.
- open interest meaning in stock market
- Open interest is the number of derivative contracts currently outstanding — positions that have been opened and not yet closed. It is not volume: volume counts transactions during the day, while open interest counts positions still alive at the end of it. If one trader opens a position and another closes one, volume rises and open interest does not move at all.
- price rising while open interest falls indicates
- Short covering — existing short positions being bought back, which lifts price without any new buying conviction behind it. That distinction matters because such a rally has a natural end point: once the covering is finished, the buying pressure disappears. Price rising while open interest also rises is the opposite case, a long buildup, where new money is entering the position.
- put call ratio above 1 means what
- A put-call ratio above 1 means more open interest is sitting in puts than in calls, and it is conventionally read contrarily as excessive fear, with readings above roughly 1.3 treated as an extreme. The serious caveat is that open interest does not record intent — a put can be bought by someone bearish or written by an institution happy to buy at that strike, and both look identical in the data.
- the strike with the highest call open interest usually acts as
- Resistance, in the standard reading, while the strike carrying the highest put open interest often acts as support. The mechanism is real: writers at those strikes hedge their exposure, and that hedging creates actual buying and selling around those levels. NSE publishes the strike-wise option chain live and free, and on the NIFTY the effect is most visible at round strikes.
- is max pain theory reliable
- Max pain — the strike at which the largest rupee value of options would expire worthless — rests on a real but weak mechanism and is not a forecast. Hedging by option writers does exert some pull near expiry, but the effect is inconsistent and easily swamped by any genuine news. The level itself also shifts as open interest changes, so Monday’s number is frequently a different strike by Thursday.