Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Yext Inc (YEXT), where a total volume of 2,973 contracts has been traded thus far today, a contract volume which is representative of approximately 297,300 underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 50.3% of YEXT's average daily trading volume over the past month, of 591,515 shares. Particularly high volume was seen for the $17.50 strike put option expiring January 17, 2020, with 911 contracts trading so far today, representing approximately 91,100 underlying shares of YEXT. Below is a chart showing YEXT's trailing twelve month trading history, with the $17.50 strike highlighted in orange:

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

Seattle Genetics Inc (SGEN) saw options trading volume of 5,111 contracts, representing approximately 511,100 underlying shares or approximately 49.4% of SGEN's average daily trading volume over the past month, of 1.0 million shares. Particularly high volume was seen for the $125 strike call option expiring January 17, 2020, with 2,008 contracts trading so far today, representing approximately 200,800 underlying shares of SGEN. Below is a chart showing SGEN's trailing twelve month trading history, with the $125 strike highlighted in orange:

And Sprint Corp (S) saw options trading volume of 71,559 contracts, representing approximately 7.2 million underlying shares or approximately 49.3% of S's average daily trading volume over the past month, of 14.5 million shares. Especially high volume was seen for the $7 strike call option expiring December 20, 2019, with 54,364 contracts trading so far today, representing approximately 5.4 million underlying shares of S. Below is a chart showing S's trailing twelve month trading history, with the $7 strike highlighted in orange: