Among the underlying components of the S&P 500 index, we saw noteworthy options trading volume today in Norfolk Southern Corp (NSC), where a total of 5,197 contracts have traded so far, representing approximately 519,700 underlying shares. That amounts to about 44.9% of NSC's average daily trading volume over the past month of 1.2 million shares. Particularly high volume was seen for the $195 strike put option expiring October 27, 2023, with 1,008 contracts trading so far today, representing approximately 100,800 underlying shares of NSC. Below is a chart showing NSC's trailing twelve month trading history, with the $195 strike highlighted in orange:

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Today's Most Active Call & Put Options of the S&P 500 »

Blackrock Inc (BLK) options are showing a volume of 2,958 contracts thus far today. That number of contracts represents approximately 295,800 underlying shares, working out to a sizeable 44.6% of BLK's average daily trading volume over the past month, of 662,855 shares. Particularly high volume was seen for the $615 strike call option expiring November 10, 2023, with 503 contracts trading so far today, representing approximately 50,300 underlying shares of BLK. Below is a chart showing BLK's trailing twelve month trading history, with the $615 strike highlighted in orange:

And Allstate Corp (ALL) options are showing a volume of 6,793 contracts thus far today. That number of contracts represents approximately 679,300 underlying shares, working out to a sizeable 44.1% of ALL's average daily trading volume over the past month, of 1.5 million shares. Especially high volume was seen for the $120 strike put option expiring November 17, 2023, with 2,768 contracts trading so far today, representing approximately 276,800 underlying shares of ALL. Below is a chart showing ALL's trailing twelve month trading history, with the $120 strike highlighted in orange: