Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Zebra Technologies Corp. (ZBRA), where a total volume of 1,369 contracts has been traded thus far today, a contract volume which is representative of approximately 136,900 underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 64.5% of ZBRA's average daily trading volume over the past month, of 212,105 shares. Especially high volume was seen for the $600 strike call option expiring January 21, 2022, with 112 contracts trading so far today, representing approximately 11,200 underlying shares of ZBRA. Below is a chart showing ZBRA's trailing twelve month trading history, with the $600 strike highlighted in orange:

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

Vertex Pharmaceuticals, Inc. (VRTX) options are showing a volume of 9,003 contracts thus far today. That number of contracts represents approximately 900,300 underlying shares, working out to a sizeable 59.7% of VRTX's average daily trading volume over the past month, of 1.5 million shares. Especially high volume was seen for the $220 strike call option expiring December 17, 2021, with 2,532 contracts trading so far today, representing approximately 253,200 underlying shares of VRTX. Below is a chart showing VRTX's trailing twelve month trading history, with the $220 strike highlighted in orange:

And Cisco Systems Inc (CSCO) saw options trading volume of 81,830 contracts, representing approximately 8.2 million underlying shares or approximately 59.6% of CSCO's average daily trading volume over the past month, of 13.7 million shares. Especially high volume was seen for the $58 strike call option expiring November 05, 2021, with 8,909 contracts trading so far today, representing approximately 890,900 underlying shares of CSCO. Below is a chart showing CSCO's trailing twelve month trading history, with the $58 strike highlighted in orange: