SPYPOCT 21Open interest change
Open interest in SPY puts expiring Oct 21 (1 week out) rose 44,462 at the Oct 12 settlement
12,809 to 57,271 contracts between the Oct 9 and Oct 12 settlements, 347% of the prior figure.
SPY · PUTS · OCT 15Settled
Open interest in SPY puts expiring Oct 15 rose 92,850 at the Oct 12 settlement
As of . Source: Cboe settlement open interest archive.
69,456 to 162,306 contracts between the Oct 9 and Oct 12 settlements, 134% of the prior figure.
Evidence
| Measure | Value |
|---|---|
| Open interest, earlier settlement | 69,456 |
| Open interest, later settlement | 162,306 |
| Change (contracts) | +92,850 |
| Change as a share of the earlier figure | 134% |
| Earlier settlement | Oct 9, 2026 |
| Later settlement | Oct 12, 2026 |
| Days to expiry | 3 |
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: 92,850; Change as a share of the earlier figure: 1.3368
- Contracts traded behind each figure
- Open interest changed: 97
- Baseline
- median absolute open interest change share, contracts within a week: 0.3893
- 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 SPY snapshots, Oct 12, 2026
All SPY snapshots on the hub- SPYP779OCT 12Volume vs open interest
SPY 779 puts expiring Oct 12 (same day) traded 5.8x their open interest
SPY puts expiring that date in the strikes we track traded 1.9x their open interest, by 09:48 ET on Oct 12, 2026. Tracked: up to 40 strikes around the money across 33 expirations.
- SPYPOCT 16Put/call by expiry
SPY puts expiring Oct 16 traded 2.6x the calls on that date
15,303 put and 5,926 call contracts by 09:37 ET on Oct 12, 2026. Est. premium $2.3M puts, $2.0M calls. Tracked: up to 40 strikes around the money across 33 expirations.
- SPYOCT 12Same-day share
Same-day contracts accounted for 70% of tracked SPY option volume by 09:32 ET
62,601 of 89,969 tracked contracts on Oct 12, 2026, puts 30,306 and calls 32,295. Tracked: up to 40 strikes around the money across 33 expirations.