Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Kroger Co (KR), where a total volume of 39,193 contracts has been traded thus far today, a contract volume which is representative of approximately 3.9 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 76.2% of KR's average daily trading volume over the past month, of 5.1 million shares. Particularly high volume was seen for the $51 strike call option expiring December 02, 2022, with 2,414 contracts trading so far today, representing approximately 241,400 underlying shares of KR. Below is a chart showing KR's trailing twelve month trading history, with the $51 strike highlighted in orange:

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

Equifax Inc (EFX) saw options trading volume of 8,950 contracts, representing approximately 895,000 underlying shares or approximately 75.4% of EFX's average daily trading volume over the past month, of 1.2 million shares. Especially high volume was seen for the $175 strike put option expiring December 16, 2022, with 8,212 contracts trading so far today, representing approximately 821,200 underlying shares of EFX. Below is a chart showing EFX's trailing twelve month trading history, with the $175 strike highlighted in orange:

And Intuitive Surgical Inc (ISRG) saw options trading volume of 11,510 contracts, representing approximately 1.2 million underlying shares or approximately 56.7% of ISRG's average daily trading volume over the past month, of 2.0 million shares. Particularly high volume was seen for the $290 strike call option expiring December 16, 2022, with 2,917 contracts trading so far today, representing approximately 291,700 underlying shares of ISRG. Below is a chart showing ISRG's trailing twelve month trading history, with the $290 strike highlighted in orange: