Reconciling master and MAM subaccount reports

MAM master and subaccount reports may differ in row counts, timing and quantities without being incorrect. One instruction may become several fills or allocations. Reconciliation aims to reconstruct a reviewable relationship between a master decision and each subaccount’s outcome, not force every table to look identical.

Align scope and time first

Identify the reporting period, timezone, account type and instruments. Short symbol names do not establish equivalence; inspect contract size, settlement currency and quantity rules. A master account’s execution or allocation-recording role may also vary by implementation. Use the actual host architecture rather than an assumed model.

Instruction identifiers differ from fill identifiers

For each master instruction, find the corresponding allocation entries and subaccount fills. One order may have several partial fills, or an aggregated entry may keep details in another report. Matching only similar prices and times can fail when trades occur close together. Without an authoritative mapping, do not present the relationship as certain.

A hypothetical quantity match

Suppose a defined rule assigns a target of 0.03 lots to a subaccount. The execution report shows portions of 0.01 and 0.02. Their total is 0.03, but each portion’s price, timing and charge still need review. This is neither a recommended allocation ratio nor evidence that every host splits instructions this way.

Keep remainders and unexecuted instructions

Rounding, margin constraints, rejection or a paused subaccount may prevent full target execution. Retain the reason and status. Do not silently attribute a remainder to the next trade or another account. If a carry-forward or aggregation rule exists, its version and linked entries are necessary.

Build an allocation ledger

• Master, allocation and subaccount fill identifiers.
• Instrument mapping, order side and quantity units.
• Allocation basis and pre-rounding target.
• Submitted, executed, rejected and remaining quantities.
• Prices, timestamps, fee currency and allocation-rule version.

Matching quantities do not mean matching outcomes

Even with matched sizes, execution prices, base currencies and costs can produce different monetary results. Weight multiple fill prices by quantity. Compare open and closed results under common definitions and avoid counting currency conversion twice. Do not assign a return discrepancy to allocation error before reviewing these bases.

Keep unresolved differences explicit

Each discrepancy needs a responsible reviewer, registration time and required evidence. Record corrections with a date and reason and retain previous versions under the applicable policy. Missing data is not a zero value. A reconciliation table must not discard failed instructions to improve its appearance.

Managers can explain reconciliation with non-private samples in a cooperation inquiry. When reading trading-account information, distinguish summaries from evidence of actual account relationships. This article is not an independent audit or a claim that every platform account has live reconciliation.