SENSEX expiry 6 August 2026: what the 78,800 options did in the last 30 minutes
On Thursday 6 August 2026 the SENSEX strike nearest the index at 15:00 was 78,800. The index went from 78,789 at 15:00 to 78,955 at 15:30, up 166 points across the settle walk.
The at-the-money legs, 15:00 to 15:30
| Leg | 15:00 | High | Low | 15:30 | End vs 15:00 | Open interest |
|---|---|---|---|---|---|---|
| 78,800 CE | ₹222 | ₹472 15:24 | ₹157 15:30 | ₹157 | 0.7× | 2.4M → 1.1M |
| 78,800 PE | ₹231 | ₹252 15:03 | ₹0.7 15:30 | ₹0.7 | worthless | 2.6M → 2.3M |
Premium of the strike nearest the index at 15:00, sampled every ten seconds from the NSE option chain. Index values are the chain's own quote. Dotted verticals mark a pin-book flip on Gamma Terrain.
What happened
The 78,800 call was ₹222 at 15:00. It reached ₹472 at 15:24, 2.1× its 15:00 price. It ended at ₹157, 0.7× the 15:00 price. Open interest at the strike went from 2.4 million to 1.1 million, so positions were closed through the window.
The 78,800 put was ₹231 at 15:00. It never traded meaningfully above its 15:00 price. Its low was ₹0.7 at 15:30, less than half of where it started the half hour. It ended at ₹0.7, worthless.
Chain quotes were missing 15:00–15:01, 15:01–15:02, 15:02–15:03, 15:03–15:04, 15:04–15:05, 15:05–15:06, 15:06–15:07, 15:07–15:08, 15:08–15:09, 15:09–15:10, 15:10–15:11, 15:11–15:12, 15:12–15:13, 15:13–15:14, 15:14–15:15, 15:15–15:16, 15:16–15:17, 15:17–15:18, 15:18–15:19, 15:19–15:20, 15:20–15:21, 15:21–15:22, 15:22–15:23, 15:23–15:24, 15:24–15:25, 15:25–15:26, 15:26–15:27, 15:27–15:28, 15:28–15:29, 15:29–15:30: the exchange rate-limited the poll in the endgame, so the chart shows a hole there rather than a line. Highs and lows inside a hole are not known.
For context, across 21 NIFTY and SENSEX expiries measured to 2026-09-08, 15 of 42 at-the-money legs doubled at some point in this window, 26 lost half, and 13 ended at or above their 15:00 price. This page states what the tape did. It is not a recommendation to buy or sell anything.
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