Notable Wednesday Option Activity: ISRG, UNH, REGN

Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Intuitive Surgical Inc (ISRG), where a total volume of 2,220 contracts has been traded thus far today, a contract volume which is representative of approximately 222,000 underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 72.3% of ISRG's average daily trading volume over the past month, of 307,170 shares..