There is a particular kind of praise that a customer will never write into a testimonial form but will happily put in front of the hardest audience they have: their own investors. When a founder tells their board, in a monthly update, that your product cut their support load in half or unblocked a launch, they are not marketing for you. They are explaining their own numbers to people whose entire job is to doubt them. That is what makes an investor-update mention worth more than almost any solicited quote — and what makes it dangerous to touch. The document is confidential by default, the sentence lives inside a paragraph about the customer's own business, and the moment you ask to use it you are asking them to expose a private artifact. It can become a testimonial, but only if you treat the update as borrowed and go get a version you are actually allowed to publish.
Why an investor-update mention is unusually strong
Most testimonials are written to an audience that wants to like you: a prospect, a reader, a case-study page. An investor update is written to an audience paid to find the flaw. When a customer credits your product in that context, they are staking their own credibility on the claim — an investor will remember it and ask about it next quarter. That raises the stakes of every word, and it strips out the generosity that inflates a normal testimonial. Nobody writes "a game-changer" to their board. They write "reduced our onboarding time from three weeks to four days, which is why the Q3 numbers moved," because the board will check.
That specificity and that stakes-backed honesty are exactly what a prospect finds convincing. But they are also why you cannot lift the sentence directly. The strength comes from the frame — a private financial document — and publishing it destroys the frame while breaching the confidence. You want the claim, not the artifact.
The confidentiality problem is the whole problem
Everything about doing this well comes down to one fact: an investor update is a confidential document, and a mention inside it carries none of the permissions you need to publish. You may have seen the line because the founder forwarded it to you proudly, or a mutual investor mentioned it, or the customer pasted it into a thread to make a point. None of those is consent to quote it publicly with attribution. Treating a forwarded update as fair game is the fastest way to turn an enthusiastic customer into one who never puts you in writing again.
So the rule is the same one that governs any praise you found rather than were given: you go back and ask for a version you can use, on the record, for this purpose.
- Name what you saw and ask for a cleaner version. "I saw the line in your August update about cutting onboarding to four days — that's exactly the kind of result we'd love to feature. Could we quote you on that publicly?" You are not asking to publish the update; you are asking for the claim in a form built to be public.
- Let them restate it in their own frame. Often the founder will happily give you a sentence that says the same thing without the surrounding financials. That restatement is the testimonial — theirs, deliberate, and free of the confidential context.
- Agree on attribution before anything is written down. A named founder-and-company quote is a bigger ask than "the CEO of a Series A fintech." Let them choose, the same way you would for any quote whose specific claim you need to be able to stand behind.
If the answer is no, the line stays where you found it. A metric you cannot publish is not a loss — it is a customer relationship you did not spend to prove a point.
How to preserve the claim without leaking the document
Once you have a publishable restatement, the discipline is separation: keep the strength of the number, drop everything that belongs to the customer's private business.
- Quote the outcome, not the financials around it. "Onboarding went from three weeks to four days" is publishable. "…which is why we hit 140% net revenue retention" is the customer's confidential metric, and it is not yours to attach even if they said it to their board. When in doubt, keep the sentence about your product and cut the sentence about their P&L.
- Never publish the update itself as evidence. The temptation to screenshot the paragraph "for authenticity" is the exact move that breaks the confidence. The testimonial is the restated quote with the customer's name and consent behind it — provenance comes from that yes, not from exposing the source document. This is the same discipline you would apply to any private message you were tempted to screenshot.
- Don't reveal the investor context. "In their investor update, they said…" sounds like proof but tells every reader that you repackage private board material. Attribute the quote plainly to the customer. The fact that it originated in a high-stakes document is your reason to trust the claim, not a badge to display.
When the mention is second-hand
Sometimes you never see the update — a shared investor tells you "so-and-so raved about you to the board." That is even further from usable. You have a rumor of praise, filtered through a third party, with no wording and no consent. Do not manufacture a quote from it. What you can do is treat it as a signal to open the conversation: "I heard you'd had a good run with us — would you be up for saying a few words we could quote?" The investor's tip gets you the meeting; the testimonial still has to be given to you directly, in the customer's words, on the record. Anything else is a sentence the customer never actually said, and a manufactured quote has no provenance to stand on.
The short version
A mention in a customer's investor update is the strongest signal you will ever get that your product moved a number that matters, precisely because it was written for the one audience that checks. But the signal lives inside a confidential document, and the document is not yours. Go back, ask for a publishable restatement, keep the outcome and drop the financials, and never show the update itself. Do that and you convert the most credible private praise you will ever receive into a testimonial you are actually allowed to stand behind — without teaching your best customer that anything they write to their board might end up on your homepage.