IWMCOCT 21Open interest change
Open interest in IWM calls expiring Oct 21 rose 17,973 at the Oct 19 settlement
22,428 to 40,401 contracts between the Oct 16 and Oct 19 settlements, 80% of the prior figure.
IWM · CALLS · OCT 29Settled
Open interest in IWM calls expiring Oct 29 (1 week out) rose 37,604 at the Oct 19 settlement
As of . Source: Cboe settlement open interest archive.
On the page at squawkflow.com/options-flow/2026-10-19/iwm-calls-oct-29-2026-open-interest-change: the evidence table and the rule this settlement figure passed; and up to six other IWM snapshots from Oct 19, 2026.
3,782 to 41,386 contracts between the Oct 16 and Oct 19 settlements, 994% of the prior figure.
Evidence
| Measure | Value |
|---|---|
| Open interest, earlier settlement | 3,782 |
| Open interest, later settlement | 41,386 |
| Change (contracts) | +37,604 |
| Change as a share of the earlier figure | 994% |
| Earlier settlement | Oct 16, 2026 |
| Later settlement | Oct 19, 2026 |
| Days to expiry | 10 |
Why it fired
- Rule
- |change| >= 10000 or (>= 2000 and >= 50% of prior), and |change share| >= 2.0 x bucket median; prior OI >= 1000
- Values that cleared it
- Change: 37,604; Change as a share of the earlier figure: 9.9429
- Contracts traded behind each figure
- Open interest changed: 23
- Baseline
- median absolute open interest change share, contracts 1 to 3 weeks out: 0.1579
- Baseline window
- last 20 sessions
- Baseline n
- 20
- Claim level
- 0, a reported fact
What happened next
This snapshot is itself a settlement figure, so it has no follow-up of its own.
More IWM snapshots, Oct 19, 2026
All IWM snapshots on the hub- IWMCOCT 29Put/call by expiry
IWM calls outnumbered puts 24.0 to 1 expiring Oct 29 (1 week out), vs a 0.5 median
The median is IWM's call/put volume ratio for contracts 1 to 3 weeks out over the last 7 sessions. 25,905 call and 1,079 put contracts by 10:26 ET on Oct 19, 2026. Tracked: up to 40 strikes around the money across 33 expirations.
- IWMPOCT 30Put/call by expiry
IWM puts expiring Oct 30 (2 weeks out) traded 26.6x the calls, vs a 1.9x median
The median is IWM's put/call volume ratio for contracts 1 to 3 weeks out over the last 7 sessions. 51,346 put and 1,933 call contracts by 09:46 ET on Oct 19, 2026. Tracked: up to 40 strikes around the money across 33 expirations.
- IWMP271OCT 19Volume vs open interest
IWM 271 puts expiring Oct 19 (same day) traded 5.0x their open interest
IWM puts expiring that date in the strikes we track traded 0.4x their open interest, by 09:41 ET on Oct 19, 2026. Tracked: up to 40 strikes around the money across 33 expirations.
- IWMCOCT 26Put/call by expiry
IWM calls outnumbered puts 3.9 to 1 expiring Oct 26 (1 week out), vs a 0.5 median
The median is IWM's call/put volume ratio for contracts 1 to 3 weeks out over the last 7 sessions. 2,383 call and 612 put contracts by 09:41 ET on Oct 19, 2026. Tracked: up to 40 strikes around the money across 33 expirations.
- IWMNear vs far dates
IWM put/call volume ratio held at 1.11 within 3 weeks, against 2.88 1 to 3 months out
Within 3 weeks: 27,243 put and 24,560 call contracts. 1 to 3 months out: 5,859 put and 2,034 call contracts. By 09:36 ET on Oct 19, 2026. Tracked: up to 40 strikes around the money across 33 expirations.