Also, in terms of a stock being added to the Russell 3000 index, I think this is how it works. If I am wrong, please reply and correct me:
Once a name enters into an index such as the Russell 3000, it enters into the "trade-able universe" of certain funds. It doesn't mean they must buy it, but they can, should they chose to rebalance their portfolio and include ALXA.
This is a common practice, as it controls the risk by limiting the trade-able universe. A lot of funds follow the bigger indices such as the S&P 500, MSCI World, etc.