Spero Therapeutics (SPRO) Options Chain
NASDAQ: SPROHealth CareBiotechnology: Pharmaceutical PreparationsUSD
At close: Oct 9, 4:00 PM ET · Delayed 15 min
Expiration date
- Expiration
- Nov 20, 2026
- Days to expiration
- 41
- Share price
- $1.20
- Put/call ratio (OI)
- 1.52
- ATM implied volatility
- 264.8%
- Expected move
- ±$1.07
- Open interest (C / P)
- 42 / 64
SPRO options summary
The SPRO options chain for the November 20, 2026 expiration lists 2 call and 2 put contracts, with 41 days until expiration. Open interest stands at 42 calls and 64 puts, a put/call ratio of 1.52, which is more bearish, with puts outnumbering calls. At-the-money implied volatility near the $1.00 strike is 264.8%, which implies the market expects a move of about ±$1.07 (88.8%) in Spero Therapeutics stock by expiration.
The most open interest sits at the $1.00 call (40 contracts) and the $1.00 put (60 contracts).
Summary generated from market data by MetaCap's automated system. Methodology
SPRO options chain · November 20, 2026
| Calls | Puts | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Last | Bid | Ask | Strike | Bid | Ask | Last | |||||
| 0.25 | 0.25 | 1.15 | 1.00 | 0.00 | 0.10 | 0.05 | |||||
| 0.05 | 0.00 | 0.20 | 1.50 | 0.00 | 1.00 | 0.40 | |||||
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 SPRO put/call ratio?
For the November 20, 2026 expiration, the SPRO put/call ratio based on open interest is 1.52 (64 puts vs 42 calls). A ratio above 1 means more puts than calls.
What is SPRO's implied volatility?
At-the-money implied volatility for SPRO options expiring November 20, 2026 is about 264.8%, an annualized estimate of how much the market expects Spero Therapeutics stock to move.
How many SPRO option expiration dates are there?
SPRO has 4 listed expiration dates, from Oct 16, 2026 to Apr 16, 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.