This only happens when MM's have a Naked Short position that they do not want to cover, so whenever "news" comes out, they manipulate the stock price by spoofing (refusing to sell) at the Ask and/or "hitting the Bid" with more naked shorting:

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with so many good news for the last several days, yet I notice today's the share price was pushed down badly in early day and rescued by someone towards the end of the day but still lost a bit.

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