It is really very simple. Red is for sell, green is for buy and white for the MM. Now when I see a sale of 75,000 shares in the red a number of things come to mind.
1. Someone is selling.
2. Could it be an individual investor. On the balance of probabilities the answer must be no.
3. It is reasonable to conclude that an institutional investor has sold.
Regarding the information that is available, all one gets is the net movements in shares. An institutional investor may have traded very heavily during that quarter. They could be diseminating information through message boards so as to manipulate the small investors.
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