Well there are several reasons why this could happen,First of...

Well there are several reasons why this could happen,
First of all GDN are in a JV with NCM on their Mertondale JV. (July ann)
Second NCM manage the JV to earn 80% and they dont have to report every intersection to the GDN board but only where the program reaches a target point.
Third GDN are busy trying to aquire ground so they dont want a leak, evidenced by their holdings and recent pegging.
NCM donot have to ann unless they believe it may significantly change the company share price and they may withhold info from the market till checks and balances are done. Remeber mineral drilling is different to oil, a great result may be a drillhole down dip of a structure and requires checking.
I hold GDN.