Red flag explained · Customers and retention

Concentration not disclosed: who pays the bills?

Short answer: Most listings do not say how much revenue comes from the largest customer, affiliate program or traffic partner. That is common, which is why the checker rates it low. It is still a two-line question that can change the price, so ask it in your first message to the seller.

Updated 7 October 2026 · Checker rule CONC_UNKNOWN

When the checker raises it

Raised as low severity when the listing gives no top-customer or top-partner share.

Why it matters

For a SaaS the question is the largest customer. For an affiliate site it is the largest affiliate program, often Amazon Associates. For a newsletter it is the largest sponsor. For an agency it is the largest client.

If the answer is above 25%, treat it as the high-severity concentration flag.

A worked example

Composite example, not a real listing

Done-for-you podcast editing agency, service business
Asking price: $50,000
Average monthly revenue: $6,000
Average monthly profit: $2,100
Clients: 22 active clients
Business age: 3 years
Owner hours: 8 hours per week

Traffic or revenue sources typed in: Referral 60%, Direct 40%.

What the red-flag checker returns: payback of 23.8 months on average monthly profit, and this flag:

  1. Low Concentration not disclosed

    The listing does not say how much revenue comes from the largest customer, affiliate program or traffic partner.

    Ask: What share of revenue comes from the top 1 and top 3 customers or partners?

The same example also raises: No connected data source mentioned.

What to check

Questions to send the seller

  1. What share of revenue comes from the top 1 and top 3 customers or partners?
  2. What share of revenue comes from the top 1 and top 3 customers, partners or programs?
  3. Are any customers, partners or suppliers personal contacts of yours who may not stay after a sale?
  4. How much revenue comes from sponsors, and are any sponsors booked beyond the sale date?

Related flags

Useful next

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The checker is a set of plain rules, not an AI model, and its flags are prompts for questions, not verdicts. Composite examples are invented. Informational screening only, not investment, legal or tax advice.