Sutro Biopharma (STRO) Options Chain
NASDAQ: STROHealth CareBiotechnology: Biological Products (No Diagnostic Substances)USD
At close: Oct 9, 4:00 PM ET · Delayed 15 min
Expiration date
- Expiration
- Nov 20, 2026
- Days to expiration
- 41
- Share price
- $14.27
- Put/call ratio (OI)
- 0.68
- Put/call ratio (volume)
- 2.50
- ATM implied volatility
- 104.8%
- Expected move
- ±$5.01
- Open interest (C / P)
- 40 / 27
STRO options summary
The STRO options chain for the November 20, 2026 expiration lists 8 call and 7 put contracts, with 41 days until expiration. Open interest stands at 40 calls and 27 puts, a put/call ratio of 0.68, which is tilted bullish, with calls outnumbering puts. At-the-money implied volatility near the $15.00 strike is 104.8%, which implies the market expects a move of about ±$5.01 (35.1%) in Sutro Biopharma stock by expiration.
The most open interest sits at the $20.00 call (19 contracts) and the $30.00 put (11 contracts).
Summary generated from market data by MetaCap's automated system. Methodology
STRO options chain · November 20, 2026
| Calls | Puts | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Last | Bid | Ask | Strike | Bid | Ask | Last | |||||
| 24.75 | 13.20 | 17.40 | 12.50 | 0.00 | 4.50 | 1.15 | |||||
| — | — | — | 15.00 | 0.00 | 4.90 | 2.91 | |||||
| — | — | — | 17.50 | 0.00 | 0.00 | 2.75 | |||||
| 1.11 | 0.00 | 4.30 | 20.00 | 3.50 | 7.50 | 3.75 | |||||
| 1.05 | 0.00 | 3.90 | 22.50 | — | — | — | |||||
| 9.00 | 0.00 | 0.00 | 25.00 | 4.50 | 8.90 | 7.65 | |||||
| 1.52 | 0.00 | 2.50 | 30.00 | 9.00 | 12.70 | 8.30 | |||||
| 11.70 | 4.10 | 8.00 | 35.00 | — | — | — | |||||
| 1.00 | 0.00 | 0.00 | 40.00 | — | — | — | |||||
| 10.24 | 0.00 | 0.00 | 45.00 | — | — | — | |||||
| — | — | — | 50.00 | 0.00 | 0.00 | 27.40 | |||||
In-the-money callsIn-the-money puts. IV = implied volatility, OI = open interest (contracts). Each contract covers 100 shares. Quotes delayed at least 15 minutes.
Frequently asked questions
What is the STRO put/call ratio?
For the November 20, 2026 expiration, the STRO put/call ratio based on open interest is 0.68 (27 puts vs 40 calls), and 2.50 based on today's volume. A ratio above 1 means more puts than calls.
What is STRO's implied volatility?
At-the-money implied volatility for STRO options expiring November 20, 2026 is about 104.8%, an annualized estimate of how much the market expects Sutro Biopharma stock to move.
How many STRO option expiration dates are there?
STRO has 4 listed expiration dates, from Oct 16, 2026 to May 21, 2027.
What does "in the money" mean?
A call is in the money when the strike price is below the current share price; a put is in the money when the strike is above it. In-the-money contracts have intrinsic value and are shaded in the table.