- · Commercial due diligence examines whether the market and customer conditions that generated a target's historical earnings are likely to continue.
- · Customer concentration risk extends well beyond a single revenue percentage and requires granular analysis of margin, cash flow, and relationship dependencies.
- · Seller growth projections must be stress-tested against external market data, using triangulated sizing methods that produce ranges rather than single-point forecasts.
- · Voice of customer research and supply chain assessment each surface material risks that accounting records alone will not reveal.
A financial audit answers one question with considerable rigour: were the numbers reported accurately? It traces revenue recognition, tests the reliability of the balance sheet, and reconciles cash flows against stated earnings. That work is necessary and consequential.
The question it leaves open, however, is the one that often determines whether an acquisition succeeds or disappoints: will the conditions that produced those earnings persist through and beyond the ownership transition?
Commercial due diligence (CDD) is the discipline that addresses that question directly. As PwC Switzerland describes it, CDD "systematically analyses the opportunities and risks of a business model and thus its future viability," examining a target from a market, customer, and competition perspective in advance of a transaction. Third Bridge frames it similarly: the work investigates "the demand, purchasing behaviour, and competitive conditions that could influence future performance."
In practical terms, this means the buyer's team turns its attention to four external domains: market dynamics, customer relationships, competitive position, and supply chain resilience. Each carries its own methodology. Each can surface risks that do not appear on the income statement.
Revenue concentration in a small number of customers is a well-understood concern in M&A. Baker Tilly's research notes that a customer representing greater than 10% of a company's revenues or contribution margin presents a possible negative impact on the buyer's ability to achieve projected returns. That threshold is a useful starting point.
Where the analysis must go further is in recognising that concentration risk has several dimensions that a revenue percentage alone does not capture. As Matchpoint Partners' research illustrates, a customer may contribute modest revenue yet carry exceptional margin, account for a disproportionate share of cash collections, control a distribution channel, or depend structurally on the founder's personal relationship. Two accounts that appear unrelated may share a common budget cycle or macroeconomic shock driver, creating correlated exposure that looks diversified on the surface.
Unpacking these hidden dependencies requires granular accounts-receivable analysis and, where access permits, direct conversations with key commercial personnel. The goal is to understand what each major customer actually represents to the business's cash flow and continuity, not only its contribution to the top line.
Seller models are built to support a transaction. That observation carries no particular criticism; it is simply the nature of how deal materials are prepared. The consequence for buyers is that market growth assumptions, customer retention rates, and projected market-share gains may embed optimism that external data does not support.
A defensible market assessment requires what Umbrex's Commercial Due Diligence Playbook calls triangulated sizing: top-down and bottom-up total addressable market estimates cross-referenced against each other, with growth drivers tied to observable customer behaviour rather than generalised sector projections. The playbook is direct on one point that practitioners would recognise: "sizing is not a single number; it is a set of ranges tied to explicit definitions, methods you can replicate, and drivers you can monitor post-close."
Public data sources — census records, economic databases, industry filings — provide an external reference point against which private claims can be checked. Competitive intensity can be assessed through structured frameworks; the Herfindahl-Hirschman Index, for instance, offers a quantitative measure of market concentration that contextualises whether a target's stated competitive position is plausible.
The output of this work is a set of ranges and identified drivers, not a single growth number. That format is more honest and considerably more useful during the post-close period, when conditions can be monitored against the assumptions underwritten at signing.
Standard customer satisfaction surveys, and the Net Promoter Scores that summarise them, report how customers feel at a moment in time. EY's research on customer experience in private equity acknowledges these as "good indicators of customer sentiment." In most operating contexts, current sentiment is useful intelligence.
In a transaction context, the relevant question shifts. As Bell and Holmes articulate it, voice of customer research conducted during due diligence "reports what those customers are likely to do next, whether that is renew, expand, renegotiate or leave." That forward-looking dimension changes both the research design and the interpretation of findings.
A structured programme typically begins with an 80/20 financial analysis to identify the customers that generate the majority of revenue and margin. Detailed interviews with those accounts then explore what customers value, where they perceive service gaps, how they assess pricing, and whether the relationship carries any dependence on the current ownership or management team. A buyer who discovers mid-process that a top customer is evaluating alternatives, or that their loyalty is tied to a founder who plans to exit post-close, acquires actionable intelligence. That intelligence can inform valuation adjustments, earnout structures, or transitional arrangements before the deal closes.
Supply chain tends to receive less attention in due diligence discussions than financial performance or customer relationships, yet its scope is broad. As CrossCountry Consulting notes, supply chain is "a major M&A value driver for enabling topline growth, achieving operational synergies, preserving capital expenditures and improving cash flows," and it touches almost every corporate function as well as external stakeholders.
For buyers, this means supply chain assessment should examine network capacity, supplier concentration, contract terms, cost structure, and any bottlenecks or deferred capital expenditure that may constrain the operational thesis post-acquisition. A target that relies on a single-source supplier for a critical input, or that has deferred infrastructure investment to preserve reported margins, carries risks that will surface only after the transaction closes — unless the due diligence programme looks for them deliberately.
A seller's management presentation will describe the company's competitive advantages in the most favourable terms available. That is understandable. The challenge for buyers is that competitive position must be tested against purchasing behaviour and switching dynamics rather than accepted as stated.
Effective competitive analysis in the CDD process requires understanding the target's competitive shortlist from the customer's perspective: which alternatives customers considered, why they selected this provider, what barriers they would face in switching, and what they view as the most credible substitutes, whether those are other providers, an internal build option, or simply the decision to delay the purchase altogether.
The most reliable evidence on these questions tends to come from customer interviews, channel partner conversations, and discussions with former commercial leaders who no longer have a stake in the transaction outcome. Management teams are not well-positioned to provide unbiased competitive intelligence about their own organisation; the structure of the relationship makes objectivity difficult.
Commercial due diligence requires time, structured methodology, and access to sources beyond the data room. For the right transaction, particularly where a significant portion of the acquisition price rests on projected growth, it earns its place in the process by testing whether the assumptions embedded in that price are supportable.
The findings, when rigorous, produce not a recommendation but a more precisely calibrated view of risk and opportunity. They allow advisors and buyers to frame valuation ranges around evidence rather than projection, and to identify the post-close monitoring indicators that will confirm or challenge the investment case as events unfold.
That is the substance of the discipline: measured, methodical, and grounded in what external reality can and cannot support.
This article reflects market observations drawn from publicly available research and is intended for informational purposes only. It does not constitute investment advice or a recommendation to transact.
