Look at the daily charts. When the price moves 2 or 3 points there are inevitably a few small sales of around 200 shares at a lower offer. That drives the price down. If someone owns 50,000 or 100,000 shares and wants to accumulate more, sacrificing a few hundred shares to then be able to buy 20,000 at 2 or 3 points lower is a no brainer. The daily price moves have been very small over the last week or so , so their tactics are effective.
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