Put-Call Ratio (Open Interest) (10-Day)

Put-Call Ratio (Open Interest): The ratio of outstanding put contracts to outstanding call contracts at the close of the trading day, for options with the relevant expiration date.

Prothena Corporation plc (PRTA) had 10-Day Put-Call Ratio (Open Interest) of 0.3587 for 2026-01-16.

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Figures for 2026-01-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2783
Historical Volatility (Parkinson)	0.4181
Implied Volatility (Calls)	0.3649
Implied Volatility (Puts)	1.5959
Implied Volatility (Mean)	0.9804
Put-Call Implied Volatility Ratio	4.3731
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.0000
Put-Call Ratio (Open Interest)	0.3587