Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Redfin Corp (RDFN), where a total volume of 4,272 contracts has been traded thus far today, a contract volume which is representative of approximately 427,200 underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 45.4% of RDFN's average daily trading volume over the past month, of 940,480 shares..