Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Merck & Co Inc (MRK), where a total volume of 42,119 contracts has been traded thus far today, a contract volume which is representative of approximately 4.2 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 45.7% of MRK's average daily trading volume over the past month, of 9.2 million shares. Particularly high volume was seen for the $103 strike put option expiring December 16, 2022, with 2,630 contracts trading so far today, representing approximately 263,000 underlying shares of MRK. Below is a chart showing MRK's trailing twelve month trading history, with the $103 strike highlighted in orange:

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

Visa Inc (V) saw options trading volume of 31,678 contracts, representing approximately 3.2 million underlying shares or approximately 44.7% of V's average daily trading volume over the past month, of 7.1 million shares. Especially high volume was seen for the $240 strike call option expiring February 17, 2023, with 2,334 contracts trading so far today, representing approximately 233,400 underlying shares of V. Below is a chart showing V's trailing twelve month trading history, with the $240 strike highlighted in orange:

And FedEx Corp (FDX) saw options trading volume of 11,418 contracts, representing approximately 1.1 million underlying shares or approximately 44.4% of FDX's average daily trading volume over the past month, of 2.6 million shares. Especially high volume was seen for the $135 strike put option expiring April 21, 2023, with 734 contracts trading so far today, representing approximately 73,400 underlying shares of FDX. Below is a chart showing FDX's trailing twelve month trading history, with the $135 strike highlighted in orange: