Among the underlying components of the S&P 500 index, we saw noteworthy options trading volume today in Align Technology Inc (ALGN), where a total of 3,141 contracts have traded so far, representing approximately 314,100 underlying shares. That amounts to about 46% of ALGN's average daily trading volume over the past month of 682,570 shares. Especially high volume was seen for the $840 strike call option expiring February 25, 2022, with 905 contracts trading so far today, representing approximately 90,500 underlying shares of ALGN. Below is a chart showing ALGN's trailing twelve month trading history, with the $840 strike highlighted in orange:

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

American Water Works Co, Inc. (AWK) options are showing a volume of 3,862 contracts thus far today. That number of contracts represents approximately 386,200 underlying shares, working out to a sizeable 45.7% of AWK's average daily trading volume over the past month, of 844,470 shares. Especially high volume was seen for the $170 strike call option expiring February 18, 2022, with 2,147 contracts trading so far today, representing approximately 214,700 underlying shares of AWK. Below is a chart showing AWK's trailing twelve month trading history, with the $170 strike highlighted in orange:

And Hilton Worldwide Holdings Inc (HLT) options are showing a volume of 8,653 contracts thus far today. That number of contracts represents approximately 865,300 underlying shares, working out to a sizeable 44.1% of HLT's average daily trading volume over the past month, of 2.0 million shares. Particularly high volume was seen for the $155 strike call option expiring May 20, 2022, with 4,012 contracts trading so far today, representing approximately 401,200 underlying shares of HLT. Below is a chart showing HLT's trailing twelve month trading history, with the $155 strike highlighted in orange: