Ann: Admission to the S&P/ASX 100 and S&P/NZX 10 Indices, page-60

Hey Soupy, no I can't really see how it's A2M's fault, the thing is A2M is officially in the 100, I've triple checked with both Macquarie and Iress, it's definitely in the list. Being in the list doesn't just happen on a piece of paper, there's a whole process that occurs, new instruments are created, funds adjust, re ratings (including by S&P). There's no way an error by A2M could force inclusion, it has to be S&P's fault.
I would say most likely what's happened is A2M was included in the 100 all along. Institutions received accurate information from Standard and Poors (ASX has no part in the process) and all the normal processes occurred. If they didn't there's no way yesterdays volume would have been as high as it was.

Then in the official public release by S&P (which is the same release that goes out later from the ASX), an error was made relating to the 100. Neither S&P or the ASX picked up on it (Not really the ASX's responsibility to pick up on it though). As a result, it was never corrected.

I think the TTS exclusion will also have a role to play.

Cheers