Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Riot Platforms Inc (RIOT), where a total volume of 81,309 contracts has been traded thus far today, a contract volume which is representative of approximately 8.1 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 45.3% of RIOT's average daily trading volume over the past month, of 18.0 million shares. Especially high volume was seen for the $11 strike call option expiring September 08, 2023, with 6,153 contracts trading so far today, representing approximately 615,300 underlying shares of RIOT. Below is a chart showing RIOT's trailing twelve month trading history, with the $11 strike highlighted in orange:

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

Avantor Inc (AVTR) saw options trading volume of 19,840 contracts, representing approximately 2.0 million underlying shares or approximately 45.2% of AVTR's average daily trading volume over the past month, of 4.4 million shares. Particularly high volume was seen for the $17.50 strike put option expiring November 17, 2023, with 13,478 contracts trading so far today, representing approximately 1.3 million underlying shares of AVTR. Below is a chart showing AVTR's trailing twelve month trading history, with the $17.50 strike highlighted in orange:

And Universal Technical Institute, Inc. (UTI) saw options trading volume of 473 contracts, representing approximately 47,300 underlying shares or approximately 44.5% of UTI's average daily trading volume over the past month, of 106,400 shares. Particularly high volume was seen for the $7.50 strike call option expiring October 20, 2023, with 460 contracts trading so far today, representing approximately 46,000 underlying shares of UTI. Below is a chart showing UTI's trailing twelve month trading history, with the $7.50 strike highlighted in orange: