In my opinion, the 5 existing institutions shorted most of the shares they bought. It is near a safe bet for profit as you can get. Thus short at $5 and cover with newly minted shares at $4.35. The only requirement is to have the liquidity to cover the margin requirements in case the stock zooms up strongly before the shares are transferred to your account.
The FINRA short data shows the following as short volume.
What is quite interesting is that not more shorts were piled on Friday. The stock did get up to around $5 and traded above $4.75 for quite a while. Perhaps shorts are getting wise?
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