Ann: Operational Update, page-6

I always believed it was the MAO who ultimately determined whether an announcement is 'market sensitive'.

"When an announcement is received by the MAO, it is quickly reviewed on-screen by specialist staff to determine:

.....

Whether it is likely to be market sensitive - in which case, the MAO will initiate a brief halt to trading ..."

Page 6 of

http://www.asx.com.au/documents/rules/gn14_asx_market_announcements_platform.pdf

The way I thought of it is that the company disclosures information they think is market sensitive and then the MAO decides whether it is or not.

I could be totally wrong, but that is how I read that part of Guidance Note 14.