Put-Call Ratio (Open Interest) (20-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.

Regeneron Pharmaceuticals, Inc. (REGN) had 20-Day Put-Call Ratio (Open Interest) of 0.9206 for 2026-10-16.

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Figures for 2026-10-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3310
Historical Volatility (Parkinson)	0.2959
Implied Volatility (Calls)	0.3958
Implied Volatility (Puts)	0.4037
Implied Volatility (Mean)	0.3998
Put-Call Implied Volatility Ratio	1.0200
Implied Volatility Skew	0.0060
Option Statistics
Put-Call Ratio (Volume)	0.1329
Put-Call Ratio (Open Interest)	0.9206