What criteria are being used to determine "immediate rebalancing"? Since the index fund doesn't trade yet, it is ok to do this kinds of actions, but rebalancing without warning is a strict no-no once the actual index launches. Otherwise people will quickly lose trust in the index. I hope the ICONOMI team realizes this. The market should always get a heads up on when and how rebalancing takes place. Look up how stocks get added to S&P500 as a reference.