# Open interest in SPX puts expiring Oct 22 rose 126,840 at the Oct 21 settlement

As of the Oct 21, 2026 settlement: Open interest in SPX puts expiring Oct 22 rose 126,840 at the Oct 21 settlement.
On the page at https://squawkflow.com/options-flow/2026-10-21/spx-puts-oct-22-2026-open-interest-change: the evidence table and the rule this settlement figure passed; and up to six other SPX snapshots from Oct 21, 2026.

106,128 to 232,968 contracts between the Oct 20 and Oct 21 settlements, 120% of the prior figure. Source: Cboe settlement open interest archive.

- Session: 2026-10-21
- Kind: Open interest change
- Status: Settled
- Expiry: 2026-10-22 (within a week)
- Rule: |change| >= 10000 or (>= 2000 and >= 50% of prior), and |change share| >= 2.0 x bucket median; prior OI >= 1000
- Baseline: median absolute open interest change share, contracts within a week, last 20 sessions, n = 20, value 0.1865

| Metric | Value |
|---|---:|
| changeShare | 1.1952 |
| daysToExpiry | 1 |
| openInterest | 232968 |
| openInterestChange | 126840 |
| priorOpenInterest | 106128 |
| priorSettlement | 2026-10-20 |
| settlement | 2026-10-21 |

## What happened next

This snapshot is itself a settlement figure.

Caveat: Open interest change, not trades; it does not say which side opened or closed.

Session page: https://squawkflow.com/options-flow/2026-10-21

## Citation

Source: SquawkFlow, https://squawkflow.com/options-flow/2026-10-21/spx-puts-oct-22-2026-open-interest-change
Retrieved: 2026-10-23 03:39 ET
Attribution: cite the page URL rather than a copied number. Levels are
recomputed every session, so a number without its date is wrong within a day.

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