a procedure followed in a certain clearing and settlement systems in which transfers of securities and funds are settled on a net basis, at the end of the processing cycle, with all transfers provisional until all participants have discharged their settlement obligations. If a participant fails to settle, some or all of the provisional transfers involving that participant are deleted from the system and the settlement obligations from the remaining transfers are then recalculated. Such a procedure has the effect of allocating liquidity pressures and losses from the failure to settle to the counterparties of the participant that fails to settle. Unwinds can be distinguished from debits to securities accounts that do not imply the original transfer is rescinded (e.g. in cases where securities are discovered to be forged or stolen).