How reading the actual customer and supplier contracts, not just the financial summary, catches forward-looking risks that a purely numbers-driven FDD review will always miss.
You can build a technically flawless EBITDA bridge, a beautifully colour-coded customer concentration table, and a revenue schedule that reconciles to the penny - and still miss the single most important risk in the deal, because it was never a number in the first place. It was a clause. Key contract review is the part of financial due diligence that sits closest to the legal workstream, and it consistently rewards the analyst who is willing to stop reading the summary tab and open the actual document.
The discipline matters because a P&L is a record of what has already happened, whereas a contract is a statement about what is allowed to happen next. A buyer is not paying for last year's revenue. They are paying for the durability of next year's. And durability lives in the terms.
A revenue schedule tells you a customer generated €2m last year. It does not tell you whether that €2m is contractually committed for another three years, cancellable on thirty days' notice, or up for competitive re-tender next quarter. Two customers with identical historical revenue can carry wildly different forward risk, and the entire difference is invisible in the databook.
This is the conceptual heart of contract review: historical revenue and contractual revenue are not the same thing. A strong quality of earnings assessment treats reported revenue as a starting hypothesis, then asks how much of it is genuinely repeatable. Contracts are where that question is answered. A management team summarising its own top accounts has every incentive to describe a terminable-at-will arrangement as a "long-standing partnership". The document itself does not have that incentive.
A management-prepared contract summary is an argument. The contract is the evidence. When the two disagree, the disagreement is itself a finding.
When you open a key customer or supplier agreement, you are hunting for a specific short list of clauses. Reading a fifty-page master services agreement cover to cover on every account is neither feasible nor useful; knowing exactly what you are looking for is the whole skill.
Consider three customers, each generating exactly €2.0m of revenue in the last twelve months. On a concentration table they look identical. Read the contracts and they diverge completely.
| Customer | Revenue (LTM) | Contract term | Termination | Change-of-control | Forward risk |
|---|---|---|---|---|---|
| Alpha | €2.0m | 3 yrs remaining, fixed price | For cause only | Silent (survives) | Low - genuinely committed |
| Beta | €2.0m | Evergreen, auto-renew | 30 days for convenience | Silent | High - effectively month-to-month |
| Gamma | €2.0m | 18 months remaining | For cause | Consent required on CoC | Deal risk - customer can walk at signing |
All three contribute the same €2m to trailing EBITDA. But if you are modelling forward revenue, Alpha's €2m is close to bankable, Beta's should be haircut heavily for cancellation risk, and Gamma's is contingent on the transaction itself - the customer holds a consent right triggered by the very deal you are diligencing. A concentration table showing "€6m across three customers, 45% of revenue" hides all of this. The contracts reveal it.
That single Gamma finding - a change-of-control consent on a top-three account - can move deal terms materially, whether through a specific warranty, a price chip, or a condition to completion. It is exactly the kind of insight that justifies independent diligence, and it comes from reading, not calculating.
The materiality of contract review scales directly with concentration. If a target's top three customers represent 60% of revenue, those three agreements are close to the most important documents in the entire data room - each deserves genuine, line-by-line review rather than a single row in a summary table.
The logic is simple risk-weighting. A clause buried in a contract representing 0.5% of revenue is a rounding error. The same clause in a contract representing 25% of revenue is potentially deal-defining. This is why sensible contract-review scoping is revenue-weighted: you request the top N accounts by revenue, not a random sample, and you spend your reading time where the exposure actually sits. The link to customer concentration work is not incidental - the concentration analysis is what tells you which contracts to read, and reading the contracts is what turns a concentration percentage into an actual risk verdict.
In practice, contract review on an FDD engagement follows a repeatable rhythm that sits inside the broader financial due diligence process:
The output is not "we read the contracts." It is a schedule of specific, quantified exposures tied back to accounts and revenue - the format that actually feeds the FDD report structure and gives the deal team something to act on.
Contract review is not a standalone legal curiosity; its findings ripple through the financial analysis. A for-convenience termination right on a large account should inform how you present revenue quality and how much weight the model's forecast deserves. A change-of-control clause on a lender facility or a key customer becomes a completion-mechanics point that interacts with the net debt position and the day-one financing plan. Onerous supplier terms - cash-on-delivery, shortened payment windows, minimum purchase commitments - feed directly into working-capital analysis and the normalised working-capital target.
The best analysts close the loop explicitly. They do not leave "contract terminable on 30 days' notice" sitting in the legal appendix; they carry it into the earnings discussion and say, in effect, this is why we would not treat this revenue as fully durable. That is the difference between a review that reads contracts and a review that uses them.
There is a two-way traffic here worth naming. Contracts do not just receive scrutiny from the financial analysis; they redirect it. A minimum-volume commitment discovered in a supply agreement tells you where to probe the cost base. A most-favoured-nation pricing clause on a major customer tells you the reported margin may not be defensible if the account grows. An unusual rebate or retrospective-discount mechanism buried in a distribution contract can explain a revenue trend the numbers alone made look like organic growth. In each case the document sends you back to the model with a sharper question than you would otherwise have asked. This is why experienced practitioners treat contract review and financial analysis as a single iterative loop rather than two sequential tasks: each pass through the documents refines the numbers, and each pass through the numbers tells you which documents to reread.
Contract review is tedious, unglamorous work. Reading dense legal prose for a specific short list of clauses is genuinely less satisfying than building a polished bridge. But it is precisely the terrain where patient, careful analysts consistently find what spreadsheet-only reviewers miss - and it is a hard skill that separates a diligence professional from a data processor.
It also compounds. Once you have read a few hundred customer contracts, you develop pattern recognition: you know which industries default to evergreen terms, where for-convenience rights are standard, and which clauses tend to hide in the schedules rather than the body. That intuition makes every subsequent review faster and sharper, and it is exactly the kind of judgement that is hard to teach and valuable to possess.
Interviewers love contract review because it tests whether you understand the forward-looking nature of diligence rather than just the mechanics of normalisation. Expect something like: "A target's top customer generated €3m last year. Management says it's a stable, long-term relationship. What do you actually want to check?"
"I'd start by separating historical revenue from contractual revenue - the €3m tells me what happened, not what's committed. I'd request the executed contract, not a summary, and read it against a short checklist: what's the remaining term, is it evergreen or does it need active renewal, and crucially can the customer terminate for convenience or only for cause? A thirty-day for-convenience right would mean I treat that €3m as effectively month-to-month, however 'stable' the relationship sounds. Then I'd look for a change-of-control clause, because if the customer can terminate specifically because of our transaction, that's a completion issue, not just a revenue-quality point - it might need a warranty or a condition in the SPA. Finally I'd reconcile whatever management's summary claims against what the document actually says, because a gap between the two is itself a finding. The headline number is where I start, but the contract is where I'd form my view on how much of it I'd trust going forward."
That answer works because it does three things at once: it distinguishes historical from contractual revenue, it names the specific clauses that matter, and it connects the finding to deal mechanics rather than leaving it as an abstract observation.
The revenue schedule tells you what a business earned. The contracts tell you what it is entitled to keep. In a deal where the top handful of accounts drive the economics, the gap between those two statements is often the most important thing you will find - and you will only find it if you put down the spreadsheet and read. The analyst who does the boring, patient work of reading the actual documents is the one who says, "this customer can walk with thirty days' notice, not the twelve-month term management described" - and that sentence, on its own, can be worth more than the entire rest of the report.
The Transaction Services Interview Programme (€119.99, one-time) includes a full contract-review module: the clause checklist we use on live engagements, revenue-weighted scoping drills, and worked examples of translating termination and change-of-control findings into deal-ready language. Enrol today.
Hundreds of candidates prepared their interviews with this programme. Those who landed the role have one thing in common: they worked the cases before walking into the room.
