When DTC receives instructions to effect a transaction, it may first be processed through one of several DTC systems before any DTC accounts are updated. For example, a transaction involving a delivery of securities may first be processed through one or more of the following:
- The IPO Tracking System
- The Receiver Authorized Delivery (RAD) system
- The Money Market Instrument (MMI) system.
After the transaction is processed, it is entered into DTC's Account Transaction Processor (ATP) system, where it is checked for various criteria (see Reasons for Recycling) before it is completed.
One critical function of ATP is Recycle Processing, also referred to as Pend Processing. DTC's recycle processor holds Participant transactions that cannot immediately complete. All transaction types recycle if they cannot immediately complete, except:
- Minimum amount (MA) to net additions (NA) moves (using Collateral Moves functions)
- Releases of collateral
- Memo segregations (using the Memo Segregation functions)
- Segregations (using the Account Segregation Releases function)
- Transactions input with the "prevent pend" option (see below).
Note: These transactions will be dropped if they cannot complete when ATP performs its initial check.