Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Cleveland-Cliffs Inc (CLF), where a total volume of 242,343 contracts has been traded thus far today, a contract volume which is representative of approximately 24.2 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 93.6% of CLF's average daily trading volume over the past month, of 25.9 million shares. Especially high volume was seen for the $26 strike call option expiring August 13, 2021, with 21,832 contracts trading so far today, representing approximately 2.2 million underlying shares of CLF. Below is a chart showing CLF's trailing twelve month trading history, with the $26 strike highlighted in orange:

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

Athersys Inc (ATHX) saw options trading volume of 13,448 contracts, representing approximately 1.3 million underlying shares or approximately 92.3% of ATHX's average daily trading volume over the past month, of 1.5 million shares. Especially high volume was seen for the $1 strike call option expiring January 21, 2022, with 5,246 contracts trading so far today, representing approximately 524,600 underlying shares of ATHX. Below is a chart showing ATHX's trailing twelve month trading history, with the $1 strike highlighted in orange:

And BrightSpire Capital Inc (BRSP) saw options trading volume of 2,861 contracts, representing approximately 286,100 underlying shares or approximately 92% of BRSP's average daily trading volume over the past month, of 310,990 shares. Especially high volume was seen for the $10 strike put option expiring August 20, 2021, with 2,571 contracts trading so far today, representing approximately 257,100 underlying shares of BRSP. Below is a chart showing BRSP's trailing twelve month trading history, with the $10 strike highlighted in orange: