Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Tripadvisor Inc (TRIP), where a total volume of 10,384 contracts has been traded thus far today, a contract volume which is representative of approximately 1.0 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 48.8% of TRIP's average daily trading volume over the past month, of 2.1 million shares. Especially high volume was seen for the $34 strike put option expiring January 21, 2022, with 1,113 contracts trading so far today, representing approximately 111,300 underlying shares of TRIP. Below is a chart showing TRIP's trailing twelve month trading history, with the $34 strike highlighted in orange:

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

CVS Health Corporation (CVS) options are showing a volume of 25,415 contracts thus far today. That number of contracts represents approximately 2.5 million underlying shares, working out to a sizeable 48.4% of CVS's average daily trading volume over the past month, of 5.3 million shares. Especially high volume was seen for the $77 strike put option expiring August 13, 2021, with 3,295 contracts trading so far today, representing approximately 329,500 underlying shares of CVS. Below is a chart showing CVS's trailing twelve month trading history, with the $77 strike highlighted in orange:

And Silvergate Capital Corp (SI) options are showing a volume of 3,058 contracts thus far today. That number of contracts represents approximately 305,800 underlying shares, working out to a sizeable 48.1% of SI's average daily trading volume over the past month, of 635,665 shares. Particularly high volume was seen for the $95 strike put option expiring August 20, 2021, with 250 contracts trading so far today, representing approximately 25,000 underlying shares of SI. Below is a chart showing SI's trailing twelve month trading history, with the $95 strike highlighted in orange: