They have a time period of three days to cover or "locate" a borrow. Alan just recently posted information about large brokerages settlement with the SEC for using false locate programs (think: in the morning the brokerage issues a report saying that there are 1,000,000 shares available for borrow, and then 10 brokers each rely on the entire 1,000,000 shares. Just a facade of accountability.

If the locate was a real locate, then that short transaction is a legitimate short. A trader that truly believes that the stock value will be driven down. A trader that intends to be "declared" and stand behind his risk. A trader that will declare his profit by closing his transaction.