I think you are right about someone was expecting something, but I am not sure they have benefited. Buying at above $2.30 and selling at well below $2, that is a tough way to make money.
The only thing to my mind that fits the recent volume and price spike, which would have gone much higher had AEF not sat on the offer at between $2.30 and $2.40, is that Cogstate has been in discussions about being taken over, this has leaked and people positioned for it and now those discussions have broken down. So those 8.5 million or so excess shares that where bought in the last 10 or 12 days are in the process of being dumped.
If it was a negative operational issue or large trial cancellation, firstly I don't think it would have such an effect and it would also not account for last weeks abnormal trading.
CGS Price at posting:
$1.63 Sentiment: Buy Disclosure: Held
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