Post-trade processing. Each securities transaction goes through post-trade processing during which the details of the trade are compared, cleared, and settled. This involves matching the details of the buy order with those of the sell order, changing the records of ownership, and finalizing the payment. By Damian Bierman, Global Co-Chair, Asia Pacific Technical Committee, FIX Trading Community, and Head of Asia-Pacific, Portfolio Management & Trading Solutions, FactSet. Regulators should recognise the properties of the FIX protocol in their discussions about the merits of introducing pre-trade allocation rules. Allocation. The Allocation screen is used for allocating non-trade transactions (for example, Exercise, Assignment, Delivery, Cash Settlement, Expired Options, Future from Exercise and Future from Assignment) to the appropriate main and/or trading account, as well as the ability to edit previously allocated transactions.