Customer concentration is one of the few things that can quietly discount the value of an otherwise healthy company. The logic is familiar: if one customer leaves, a large share of the revenue leaves with it, and an acquirer buying that revenue is buying that risk.
We define a lowball as an offer of two times earnings or less. In a recent sample of Value Builder data covering nearly 3,000 owners of £1m+ companies, about 10% of those whose largest customer accounted for less than 15% of revenue drew a lowball. Among owners whose largest customer represented more than half of revenue, about 30% did. In other words, you are around three times more likely to get lowballed if you have a major customer concentration problem.
That question asks about a customer. But a customer is only one way revenue gets concentrated, and it is not always the most dangerous one.
Consider Dane Pan. He and his wife built Monet Brands to £1 million in revenue on a £20 skincare tool with a landed cost of £4.50. Two employees, margins of 18 to 20%, and about an hour a week of Dane’s time. By the numbers, close to an ideal small company.
It also ran 88% of its revenue through Amazon.
Why a Platform Counts
Amazon never bought anything from Monet Brands. Thousands of individual shoppers did, one order at a time. On paper, that is the opposite of concentration.
But the exposure that gets priced in a transaction is not the number of customers. It is the number of parties that can unilaterally switch off the revenue. A platform qualifies. Amazon can rewrite the policies governing a category, suspend a listing pending an investigation, or adjust an algorithm and move a product from page one to page four. None of that requires ill will toward a seller. It requires a decision about Amazon’s own business.
A customer has to be persuaded to leave, and the exit is usually visible months out. A platform changes the terms overnight and sends notice afterwards. Dane understood this, and it was part of why he decided to sell.
What Happened When He Sold
They listed in May 2025. Nine buyers cleared the proof-of-funds screen. Four wrote letters of intent, ranging from two times SDE to four times.
Same company, same quarter, same financials, and a factor of two between the best offer and the worst. One of the four was a lowball.
Three of the four LOIs carried holdbacks, with 20 to 30% of the price contingent on hitting targets after closing. The targets were tied to sales. A sales-based earnout on an Amazon business asks a seller to keep carrying platform risk after surrendering control of the company. Dane’s fractional CFO put the right test on it: treat an earnout as a bonus, and ask whether the deal still works if that money never arrives.
All cash at close was the non-negotiable. Two buyers would not move, and those two deals died. Of the remaining pair, one had run Amazon businesses before. That buyer had come in near four times with a holdback attached. Converting it to 100% cash at close brought the figure to 3.6 times SDE, with inventory paid at cost on top.
Monet Brands sold cleanly, to a buyer Dane trusted with the brand. The 88% did not prevent that. But it produced a lowball among the four offers, and it meant the real negotiation was fought over how much of the price was guaranteed rather than what the price was.
That is what concentration costs. Not a headline discount, but a wider spread of outcomes and more ways for a deal to go sideways.
Don’t let hidden dependencies secretly discount your life’s work just as you approach the finish line. We help founders map out these exact blind spots before they become a buyer’s leverage during negotiations. To get a clear, objective picture of where you stand, I’m offering a complimentary dependency score to pinpoint exactly where your revenue might be dangerously tied up in vulnerable channels. Let’s grab a virtual coffee to run your current setup through our endgame planning tools and make sure your final valuation stays securely in your hands.