Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Apple Inc (AAPL), where a total volume of 768,484 contracts has been traded thus far today, a contract volume which is representative of approximately 76.8 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 82.7% of AAPL's average daily trading volume over the past month, of 92.9 million shares. Especially high volume was seen for the $130 strike call option expiring May 07, 2021, with 79,886 contracts trading so far today, representing approximately 8.0 million underlying shares of AAPL. Below is a chart showing AAPL's trailing twelve month trading history, with the $130 strike highlighted in orange:

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

Boeing Co. (BA) saw options trading volume of 98,312 contracts, representing approximately 9.8 million underlying shares or approximately 77.8% of BA's average daily trading volume over the past month, of 12.6 million shares. Particularly high volume was seen for the $230 strike call option expiring May 07, 2021, with 7,914 contracts trading so far today, representing approximately 791,400 underlying shares of BA. Below is a chart showing BA's trailing twelve month trading history, with the $230 strike highlighted in orange:

And Salesforce.com Inc (CRM) options are showing a volume of 36,265 contracts thus far today. That number of contracts represents approximately 3.6 million underlying shares, working out to a sizeable 72.6% of CRM's average daily trading volume over the past month, of 5.0 million shares. Especially high volume was seen for the $240 strike call option expiring May 21, 2021, with 2,089 contracts trading so far today, representing approximately 208,900 underlying shares of CRM. Below is a chart showing CRM's trailing twelve month trading history, with the $240 strike highlighted in orange: