Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in ChemoCentryx, Inc. (CCXI), where a total volume of 21,014 contracts has been traded thus far today, a contract volume which is representative of approximately 2.1 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 58.3% of CCXI's average daily trading volume over the past month, of 3.6 million shares. Particularly high volume was seen for the $12.50 strike put option expiring August 20, 2021, with 10,022 contracts trading so far today, representing approximately 1.0 million underlying shares of CCXI. Below is a chart showing CCXI's trailing twelve month trading history, with the $12.50 strike highlighted in orange:

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

Audacy Inc (AUD) saw options trading volume of 3,632 contracts, representing approximately 363,200 underlying shares or approximately 57.5% of AUD's average daily trading volume over the past month, of 631,890 shares. Especially high volume was seen for the $5 strike call option expiring July 16, 2021, with 2,144 contracts trading so far today, representing approximately 214,400 underlying shares of AUD. Below is a chart showing AUD's trailing twelve month trading history, with the $5 strike highlighted in orange:

And Dillard's Inc. (DDS) saw options trading volume of 2,058 contracts, representing approximately 205,800 underlying shares or approximately 57.4% of DDS's average daily trading volume over the past month, of 358,490 shares. Especially high volume was seen for the $170 strike put option expiring November 19, 2021, with 1,142 contracts trading so far today, representing approximately 114,200 underlying shares of DDS. Below is a chart showing DDS's trailing twelve month trading history, with the $170 strike highlighted in orange: