Allos Therapeutics, Inc. (NASDAQ: ALTH) having met all minimum requirements was added to the NASDAQ Biotechnology Index. Being added to an index typically yields an uptick in share price and corresponding market cap as all funds, ETF’s, separate accounts etc. that mirror an index must purchase the newly added position, in this particular case the iShares NASDAQ Biotechnology Index Fund (AMEX: IBB).
Taking a look at average daily volume of ALTH shares traded is ~275K however, today one may observe the buy spike of ~540K.
If you want to see a pretty one year chart take a look at this: