MRK Options Chain Analysis

Delayed CBOE data, snapshot 2026-08-18. Spot $135.97.

Put/Call (OI)

0.78

205k P / 263k C

Put/Call (Volume)

0.41

9k P / 22k C today

30d ATM IV

26%

annualized implied move

Call wall

$140

32k contracts

Put wall

$110

26k contracts

Tail hedging

6.1×

deep-OTM puts vs calls

What the positioning says

●Call wall at $140 (32k contracts), 3% above spot — the upside strike the crowd is already parked on; often acts as near-term resistance.
●Put wall at $110 (26k contracts), 19% below spot — the hedge floor; often acts as support.
●Deep-OTM put open interest is 6.1× deep-OTM call OI — an institutional hedging ladder sits under this stock.

Open interest by strike

All expiries combined. Amber lines mark the call and put walls; the dashed line is spot.

IV term structure

At-the-money implied volatility per expiry.

Volatility smile

IV by strike — expiry 2026-09-18. A steep left side = expensive downside protection.

30-day implied volatility history

Daily ATM IV (~30 DTE bucket) collected since March 2026. Rising IV into an event = the market bracing; collapsing IV after = the crush.

Open interest by expiry

Expiry	Call OI	Put OI	P/C	Volume today
2026-08-21	33k	22k	0.67	7k
2026-08-28	4k	1k	0.35	2k
2026-09-04	2k	566	0.34	2k
2026-09-11	2k	472	0.21	1k
2026-09-18	75k	45k	0.60	2k
2026-09-25	1k	162	0.16	486
2026-10-02	28	6	0.21	156
2026-10-16	18k	18k	1.01	1k
2026-11-20	712	529	0.74	11k
2026-12-18	27k	23k	0.82	759
2027-01-15	47k	46k	0.98	2k
2027-03-19	7k	7k	1.04	817
2027-06-17	26k	18k	0.69	228
2027-12-17	8k	12k	1.40	142
2028-01-21	11k	10k	0.93	343

Source: CBOE delayed quotes, refreshed daily after US market close. Open interest is exchange-reported and lags one session. Research, not investment advice.