Amendments cancel-and-replace the resting order on the matching engine. The prior version is retained with a version bump (v1 → v2) and both states are written to the immutable audit trail. PSX circuit limits are re-validated before re-route.
NEW ORDER TICKET · MULTI-ACCOUNT
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Target Accounts0 SELECTED
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One order is routed per selected account, tagged ADMIN in the blotter and attributed to that account — not to the operator. Quantities round to 100-share lots. BUY legs are validated against account cash and SELL legs against settled positions; flagged accounts are excluded at routing. Each order is individually sealed to the audit trail under ADMIN.TICKET.