A report of the qty of shares out short is published at about 2 week intervals.
Folks believing stock overpriced and should go down can borrow YOUR (and everyones') shares from YOUR (and everyones') broker/dealer for a fee paid to the bkr/dlr (and NOT shared with you, of course because your bkr/dlr won't even tell you they are lending your shares UNLESS asked).
The purpose of the borrow is to SELL ==>> YOUR <<== (and the usual "et al") shares into the market at a high price hoping for a (or causing a) plummet in price. Since ==>> theoretically <<== there could be as much as a 100% increase in supply (N.B. that's EXCLUDING the market-markers who are allowed to short without borrowing first - i.e. "naked short". allowing a THEORETICAL infinite increase in supply), there should be a an attractive lower price at which to buy shares to "cover" the shorts sold and return them to the scoundrels that lent your shares to work against your interests (if you're a "buy and hold" type).
The twice monthly report is a "snapshot" of the situation at pre-defined appx. 2 week intervals of the total shares out in the market and the short volume not yet returned to the lender. That gives us the ability to calculate short % as well as incremental quantity and percentage change, see trends in short activity, etc.
This MAY be useful for some in deciding to buy, hold or sell.
Hope that helps.
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