Reconciling Positions With Your Prime Broker

A fund maintains its own record of every position it holds, built from its own trade capture and position-keeping systems. Its prime broker — the entity that actually holds custody of the securities and finances the positions — maintains an independent record of the same thing, built from its own systems. In principle the two should always agree exactly. In practice, trades get booked with small timing differences, corporate actions get applied on slightly different schedules, and the occasional error creeps into one side but not the other. Reconciling the two, typically every single day, is how those gaps get caught while they're still small and easy to explain.

What gets compared

• Position quantities, instrument by instrument — does the fund's book show the same number of shares or contracts the prime broker's statement shows?
• Cash balances, including any financing or margin the broker is providing against the positions.
• Corporate action adjustments — a split, dividend, or merger should be reflected identically on both sides, on the same effective date.
• Pending trades and settlement status — trades that executed but haven't settled yet should appear as pending on both sides, not confirmed on one and missing on the other.

Why discrepancies happen even when nothing is "wrong"

Many breaks are timing differences rather than actual errors — a trade booked at the end of the day on the fund's side might not yet be reflected on the broker's side until their own overnight processing runs. These usually resolve themselves the next day. The reconciliation process exists to distinguish those harmless timing breaks from genuine discrepancies — a booking error, a failed trade, a corporate action applied incorrectly — that need active investigation and won't resolve on their own.

What this means in practice

Daily reconciliation against the prime broker is one of the most basic operational controls a fund runs, and it's usually one of the first things checked each morning, before the SOD position file is trusted for the day's trading. A break that goes unnoticed for even a few days can compound — trades built on top of a wrong starting position make the eventual reconciliation far harder, and can mean the fund has been running risk it didn't actually have, or missing risk it thought it didn't have.