Posted by the FileFreight team. We build a flat-rate delivery tool for digital sellers: secure per-buyer download links, per-buyer PDF stamping, and license keys. The stamping advice below is general practice for any seller whose delivery tool supports it; FileFreight's own behaviour is only what our homepage states.
If you sell PDFs — ebooks, workbooks, patterns, sheet music, study guides, templates — someone will e
Where to put it
Placement is a trade-off between visibility and respect for the product:
- Visible, on the cover or first page. The classic position: buyer's name and email near the front, in the same visual register as a "prepared for" line on a report. This is the deterrent position — anyone receiving the file sees the identity immediately, before they have read a page.
- Visible, in the footer of every page (or every few pages). Harder to crop out than a single cover line, because removing it means editing every sheet. Keep it small and quiet; a footer is a label, not a watermark across the ## When to stamp: at first download
Stamp each buyer's copy when they first download it, from the clean original — not in advance, and not by hand.
Stamping at first download matters for three practical reasons. First, you keep exactly one master file: the original stays private and unstamped, and every delivered
Why it works: deterrence, not locks
Stamping stops very little, technically. Its power is psychological, and for most sellers that is the part that matters:
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Sharing becomes attributable. Forwarding a generic file feels victimless. Forwarding a file with your own email address printed in the footer feels like handing someone your signed copy — because it is. Most casual sharing dies at exactly that moment of hesitation.
What it won't stop — the honest limits
Screenshots and photos of pages. A stamped page can be screenshotted and the stamp cropped out, or a printed page photographed. Short, high-value content — a single chart, a cheat sheet — is the most exposed. Stamping raises the effort; it does not eliminate it.
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Retyping and reformatting. Anyone determined can copy the text into a fresh document. For most products this is more work than the file costs, which is precisely the economic line stamping defends.
Two etiquette rules
Never stamp shared previews. F
The FileFreight picture, with the caveats
Per our homepage: FileFreight gives every buyer a unique, tokenized download link with per-product download limits and link expiry you set (Free: up to 25 downloads and 30 days; Pro: unlimited downloads and never-expiring links), stamps PDFs with the buyer's identity on first download, and — for products where you enable it — issues a license key with every paid order, validatable with one call (POST /api/licenses/validate) and revocable at any time. When Stripe reports a refund, the buyer's download entitlement and license keys are revoked automatically. Pro is $19/month with 0% per-sale fees; Free is $0 with a 5% per-sale fee. Payments run through your own Stripe account — we never see card details and never hold your money.
The honest caveats, because they decide whether we're the right tool: FileFreight is not a merchant of record — sales tax and VAT remain your responsibility. There is no automatic importer yet; the first 20 sellers get a free white-glove migration instead, rebuilt by hand within 48 hours. FileFreight is not a Shopify app — every product gets a standalone buy link you can put anywhere. And we are delivery-only: no marketplace, no discovery, so your buyers have to come from you.
Stamp the email, keep it to one friendly line plus a quiet footer, stamp at first download from a private original, and be honest with yourself about what it is: not a lock, but a name on the flyleaf. For most PDF sellers, that name is what stops the forwarding — no DRM required.ree samples, lead magnets, and preview chapters are meant to travel — that is their job. Stamping them is pointless (there is no buyer to attribute), off-putting to prospects, and can stamp a downloader's details onto a file you then encourage them to share. Keep previews clean and stamp only paid copies.
Treat a surfaced stamp as information, not a verdict. Before accusing a buyer, consider the ordinary explanations: they sent the file to their own second device, their assistant, or their printer. When you do write, write like a person: you found a copy with their stamp, you are asking what happened, and you are reminding them of the licence. Most buyers apologise and stop. The stamp gives you a calm, factual opening — don't waste it on a threat your terms probably don't support.
- Determined pirates. Someone running a resale or leak operation will strip, crop, or OCR around stamps as a matter of routine. Stamping is aimed at your buyers' casual sharing — statistically, where most copies escape — not at professional piracy. If your threat model is organised piracy, a stamp is one layer, not the answer.
- Files already delivered unstamped. Stamping protects copies delivered after you enable it. It does nothing for the unstamped originals already sitting in earlier buyers' inboxes.
Saying this plainly to yourself matters, because it keeps the settings sane: you are deterring casual forwarding, not building DRM, and you do not need to punish buyers with aggressive marks to achieve the deterrent effect.
- Receiving becomes uncomfortable. A recipient who opens a PDF stamped with a stranger's name knows, without any lecture, that the copy was not meant for them. Some will still read it; fewer will pass it onward, and almost none will re-upload it under their own name.
- Leaks become diagnosable. When a copy does surface on a forum, the stamp tells you which order it came from. That turns a vague "my book is everywhere" into one specific conversation with one specific buyer — and most sellers find that knowing is enough; the conversation rarely needs to be hostile.
Think of stamping the way shops think of security tags: not a vault, just a visible reason for an honest person to stay honest, and a fingerprint when someone doesn't.
copy is generated from it, so correcting a typo means replacing one file, not re-making a warehouse of pre-stamped copies. Second, the stamp always matches the actual buyer of that order — there is no inventory of personalised files to mislabel or leak. Third, it scales to the order you did not expect: the launch-day sale at 3 a.m. gets a correctly stamped copy without you touching anything.
This is how FileFreight works, per our homepage: PDFs are stamped with the buyer's identity on first download, so a leaked copy traces back to its source, and originals stay private in secure storage. Whatever tool you use, ask that specific question — is the stamp applied per buyer, at delivery, from a private original? A "watermarked PDF" you upload once, with the same mark for every buyer, is decoration, not stamping.
artwork. For workbooks, patterns, and reference documents that get printed page by page, this is often the right choice — a printed page still carries its buyer.
- Discreet: inside the document's metadata or on a final colophon page. This proves provenance after the fact — useful if you need to identify a leaked copy — but it deters almost nothing, because a buyer deciding whether to forward the file may never notice it is there. Use discreet stamping as a backup to a visible stamp, not instead of one.
Our rule of thumb: one friendly visible stamp up front, plus a small footer on content pages for anything buyers print. Never stamp across illustrations, charts, or anything the buyer paid to see clearly. A stamp that damages the product punishes the one person who paid for it.
ventually forward your file to a friend, a group chat, or a forum. You cannot make a PDF unshareable. What you can do is make every paid copy carry its buyer's name, so sharing stops being anonymous. That is PDF stamping: the buyer's identity is written onto their copy at delivery time, one file per buyer, generated from your untouched original.
Done well, stamping is nearly invisible to honest buyers and quietly discouraging to everyone else. Done badly, it defaces your product, stamps the wrong files, and promises protection it cannot deliver. Here is how to do it well — and what to expect from it.
What to stamp
Stamp the minimum that identifies the buyer and the sale:
- Buyer email address. The single most useful identifier. It is unique to the buyer, it matches your order records, and a buyer thinking of forwarding the file knows the copy points straight back at their inbox.
- Buyer name, if you collect it. Friendlier than an email on the page — "Prepared for Jane Example" reads like personalisation, not surveillance — but names are not unique, so pair it with the email or an order reference somewhere.
- Order ID or order date. This is your back-office key. When a stamped copy surfaces, the order reference lets you find the exact transaction in seconds instead of guessing which of three buyers with similar names it was.
What not to stamp: payment details, full postal addresses, phone numbers, or anything you would not want visible if the file does leak. The stamp will be read by whoever receives a forwarded copy — that is the point of the deterrent — so the stamp itself should contain nothing sensitive beyond the identity you intend to show.
One line is usually enough. A stamp that reads like a legal threat on every page trains buyers to crop, cover, or resent it. A stamp that reads like a receipt is simply believed.
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