Prothena (PRTA) Options Chain
NASDAQ: PRTAHealth CareBiotechnology: Pharmaceutical PreparationsUSD
At close: Oct 9, 4:00 PM ET · Delayed 15 min
Expiration date
- Expiration
- Jan 21, 2028
- Days to expiration
- 468
- Share price
- $8.84
- Put/call ratio (OI)
- 0.09
- Put/call ratio (volume)
- 0.94
- Expected move
- ±$6.21
- Open interest (C / P)
- 257 / 22
PRTA options summary
The PRTA options chain for the January 21, 2028 expiration lists 8 call and 4 put contracts, with 468 days until expiration. Open interest stands at 257 calls and 22 puts, a put/call ratio of 0.09, which is tilted bullish, with calls outnumbering puts. At-the-money implied volatility near the $10.00 strike is 62.1%, which implies the market expects a move of about ±$6.21 (70.3%) in Prothena stock by expiration.
The most open interest sits at the $20.00 call (157 contracts) and the $12.00 put (19 contracts).
Summary generated from market data by MetaCap's automated system. Methodology
PRTA options chain · January 21, 2028
| Calls | Puts | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Last | Bid | Ask | Strike | Bid | Ask | Last | |||||
| 8.35 | 4.00 | 9.00 | 3.00 | — | — | — | |||||
| 3.88 | 4.00 | 9.00 | 5.00 | — | — | — | |||||
| 4.00 | 3.50 | 6.00 | 7.00 | 0.00 | 0.00 | 1.70 | |||||
| 2.95 | 0.00 | 5.00 | 10.00 | 0.50 | 5.00 | 4.00 | |||||
| 2.50 | 0.00 | 5.00 | 12.00 | 2.50 | 7.50 | 4.40 | |||||
| 2.32 | 0.00 | 5.00 | 15.00 | 4.50 | 9.50 | 6.44 | |||||
| 2.12 | 0.00 | 5.00 | 17.00 | — | — | — | |||||
| 0.85 | 0.00 | 0.95 | 20.00 | — | — | — | |||||
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 PRTA put/call ratio?
For the January 21, 2028 expiration, the PRTA put/call ratio based on open interest is 0.09 (22 puts vs 257 calls), and 0.94 based on today's volume. A ratio above 1 means more puts than calls.
What is PRTA's implied volatility?
At-the-money implied volatility for PRTA options expiring January 21, 2028 is about 62.1%, an annualized estimate of how much the market expects Prothena stock to move.
How many PRTA option expiration dates are there?
PRTA has 6 listed expiration dates, from Oct 16, 2026 to Jan 21, 2028.
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.