Put-Call Ratio (Open Interest) (30-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 30-Day Put-Call Ratio (Open Interest) of 1.8963 for 2025-10-10.

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Figures for 2025-10-10

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4572
Historical Volatility (Parkinson)	0.4678
Implied Volatility (Calls)	0.7824
Implied Volatility (Puts)	1.5825
Implied Volatility (Mean)	1.1824
Put-Call Implied Volatility Ratio	2.0225
Implied Volatility Skew	0.4891
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	1.8963