Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Apple Inc (AAPL), where a total volume of 736,744 contracts has been traded thus far today, a contract volume which is representative of approximately 73.7 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 81.5% of AAPL's average daily trading volume over the past month, of 90.3 million shares. Particularly high volume was seen for the $127 strike call option expiring May 28, 2021, with 73,722 contracts trading so far today, representing approximately 7.4 million underlying shares of AAPL. Below is a chart showing AAPL's trailing twelve month trading history, with the $127 strike highlighted in orange:

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

SeaWorld Entertainment Inc. (SEAS) options are showing a volume of 6,476 contracts thus far today. That number of contracts represents approximately 647,600 underlying shares, working out to a sizeable 77.4% of SEAS's average daily trading volume over the past month, of 837,170 shares. Especially high volume was seen for the $50 strike call option expiring September 17, 2021, with 5,011 contracts trading so far today, representing approximately 501,100 underlying shares of SEAS. Below is a chart showing SEAS's trailing twelve month trading history, with the $50 strike highlighted in orange:

And bluebird bio Inc (BLUE) options are showing a volume of 7,326 contracts thus far today. That number of contracts represents approximately 732,600 underlying shares, working out to a sizeable 74.9% of BLUE's average daily trading volume over the past month, of 978,630 shares. Especially high volume was seen for the $40 strike call option expiring June 18, 2021, with 4,421 contracts trading so far today, representing approximately 442,100 underlying shares of BLUE. Below is a chart showing BLUE's trailing twelve month trading history, with the $40 strike highlighted in orange: