to give isx the benefit of the doubt they have been audited by Grant Thornton for a number of years. A financial audit is not fool proof, and I think a mid tier firm like Grant thornton likely won't have as high quality as a big4 hence this issue may have been missed by GT, particularly when ISX was a micro cap back when the performance shares were granted.
there is constant news in Australia and internationally about poor audit quality so it wouldn't surprise me if there is a historical issue with revenue recognition, particularly when the margin was only a few thousand dollars that they met that last hurdle.
ISX Price at posting:
$1.07 Sentiment: None Disclosure: Not Held