another Ihub member posted this
A "fail to deliver" occurs when a broker-dealer fails to deliver securities to the party on the other side of the transaction on settlement date. There are many justifiable reasons why broker-dealers do not or cannot deliver securities on settlement date. A broker-dealer may experience a problem that is either unanticipated or is out of its control, such as (1) delays in customers delivering their shares to a broker-dealer, (2) the inability to obtain borrowed shares in time for settlement, (3) issues related to the physical transfer of securities, or (4) the failure of a broker-dealer to receive shares it had purchased to fulfill its delivery obligations. Fails to deliver can result from both long and short sales.
Regulation SHO was designed to target potentially problematic failures to deliver. Prevention of fails is the goal of the locate requirement. Regulation SHO requires broker-dealers to identify a source of borrowable stock before executing a short sale in any equity security with the goal of reducing the number of situations where stock is unavailable for settlement. But, because the locate is usually done three days before settlement, the stock may not be available from the source at the time of settlement, possibly resulting in a fail.
Regulation SHO also requires some fail positions to be closed out. When a broker-dealer has a fail position in a "threshold security," and that fail position has persisted for 13 consecutive settlement days, the broker-dealer must take immediate steps to close-out the fail by purchasing securities of like kind and quantity. Even market makers that have such persistent fails in threshold securities must close-out their positions.
