Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in AT&T Inc (T), where a total volume of 371,381 contracts has been traded thus far today, a contract volume which is representative of approximately 37.1 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 100.5% of T's average daily trading volume over the past month, of 37.0 million shares. Particularly high volume was seen for the $34 strike call option expiring May 21, 2021, with 40,016 contracts trading so far today, representing approximately 4.0 million underlying shares of T. Below is a chart showing T'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 »

NVIDIA Corp (NVDA) options are showing a volume of 59,008 contracts thus far today. That number of contracts represents approximately 5.9 million underlying shares, working out to a sizeable 92% of NVDA's average daily trading volume over the past month, of 6.4 million shares. Particularly high volume was seen for the $600 strike call option expiring May 21, 2021, with 5,145 contracts trading so far today, representing approximately 514,500 underlying shares of NVDA. Below is a chart showing NVDA's trailing twelve month trading history, with the $600 strike highlighted in orange:

And Discovery Inc (DISCA) options are showing a volume of 89,988 contracts thus far today. That number of contracts represents approximately 9.0 million underlying shares, working out to a sizeable 89.9% of DISCA's average daily trading volume over the past month, of 10.0 million shares. Especially high volume was seen for the $37.50 strike call option expiring May 21, 2021, with 16,668 contracts trading so far today, representing approximately 1.7 million underlying shares of DISCA. Below is a chart showing DISCA's trailing twelve month trading history, with the $37.50 strike highlighted in orange: