Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in United Therapeutics Corp (UTHR), where a total volume of 4,034 contracts has been traded thus far today, a contract volume which is representative of approximately 403,400 underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 75.9% of UTHR's average daily trading volume over the past month, of 531,645 shares..