How Agencies Can Trace Leaked Proposals and Designs

Why agency work leaks

Agencies send out their best thinking before anyone has paid for it: pricing, strategy decks, campaign concepts, brand identities, mockups, renders, architectural drawings. The same file often reaches a client's marketing team, their boss, a procurement contact and two other agencies in a competitive pitch.

Most leaks aren't malicious. Someone forwards the deck to a colleague, pastes a slide into an internal doc, or shows a mockup to a supplier. But if your pricing lands on a competitor's desk, or an unreleased campaign appears online early, you can't tell where it started because everyone received identical files.

What the usual options can and can't do

• NDAs and confidentiality clauses set expectations and give you something to point to, but they don't tell you which copy leaked.
• Visible watermarks (a "DRAFT" stamp or the recipient's name across the page) discourage casual sharing, but they can be cropped out of a screenshot and they make work look less polished. See visible vs invisible watermarks.
• Link-based sharing with view tracking shows who opened a proposal. It doesn't help once someone downloads or screenshots it. See our comparison with DocSend alternatives.
• File metadata disappears when the file is re-saved, exported or screenshotted.

The approach: one invisibly marked copy per recipient

An invisible forensic watermark is a pattern written into the pixels of an image or the pages of a PDF that isn't meant to be visible at normal viewing size. If each recipient gets a copy with a different pattern, every copy carries its own label. Later, you upload the file you found, and Markedfile reports which copy it matches.

It doesn't prevent sharing. It makes sharing traceable, and recipients who know that files are individually marked tend to be more careful.

How to set it up

1. Export the final proposal or design. Use a PDF for decks and proposals, and a JPEG or PNG for mockups and visuals. Do this after your last edit, because changing the file afterwards means marking again.
2. Create one marked copy per recipient. In Markedfile you upload the file and create a copy for each client, prospect or agency in the pitch. Use a neutral label you'll recognize later, such as a project code, and keep that list private.
3. Send each recipient their own copy through the channel you already use: email, a shared folder, a messaging app.
4. If something leaks, get the version you found: the file, or a screenshot or photo of it.
5. Upload it to Detect. Markedfile reports which recipient's copy it matches.

There's also a short page for the document case: mark a board or investor deck.

Files are processed in memory and are not stored. The Free plan covers 5 active files, detection for 6 months, and PDFs up to 10 pages. Longer proposals need a paid plan: Pro ($9.99/month) allows PDFs up to 50 pages, Unlimited ($19.99/month) up to 100 pages, and the Enterprise plan ($49.99/month, one shared workspace for the whole team) up to 500 pages. If your agency wants to mark files from its own tools or project workflow, the Enterprise plan includes POST /api/v1/mark and POST /api/v1/detect; see the docs.

What to do after a match

A match tells you which copy a file came from. It doesn't prove who shared it: the contact may have forwarded it on purpose, a colleague may have received it, or an inbox may have been compromised.

• Start with a calm conversation with the client, showing where you found the material.
• Check what leaked. One public mockup is different from a full pricing proposal in a competitor's hands.
• Decide what changes. For example, you might send final pricing only on request, share concepts in a call before sending files, or add a clause that individual copies are traceable.
• Don't accuse anyone based only on a match.

Where this approach has limits

• Only marked copies can be traced. A proposal you already sent unmarked can't be matched later. If the current version matters, mark it and send it again.
• Detection is never guaranteed. Heavy editing, strong compression or a very small crop can destroy a mark. Images smaller than 96×96 pixels are not accepted. Older patterns are not detected, so those files have to be marked again. A crop of about 256 px of a detailed photo or diagram is the approximate minimum, not a ceiling. A heavily compressed or heavily textured copy can still miss.
• PDF screenshots: upload the PDF file when you have it. A screenshot or photo of a page is best effort and is not guaranteed while that detection is being improved. A crop of only a barcode or QR code is not detected. Files marked with an older pattern need to be marked again.
• Resized images: images marked before the latest resize improvement need to be marked again before a resized copy can resolve, and a resize can still miss on a heavily textured image.
• Video, audio and source files aren't covered. Markedfile works with images and PDFs. Export motion work and layered files to a PDF or image if you want to mark a version.
• It identifies a copy, not a person. Treat it as a lead.

FAQ

Can I stop a client from forwarding my proposal? Not technically. You can make forwarding traceable.

Will the mark change how my design looks? It's designed to be invisible at normal viewing size. Compare the original and the marked copy on a screen you trust before sending.

Do I need a separate copy for each person at the client? It's the most precise option. If that's too many, use one copy per company or per department; you'll still know which group a leak came from.

What about competitive pitches with several agencies? Each agency or client should get its own marked copy of your material. You'll be able to tell which copy a leaked file came from.

What if the file is Figma, Keynote or PowerPoint? Export it to PDF or an image first. Markedfile works with images and PDFs.

What if I already sent the proposal without a mark? That copy can't be traced. Mark it and send the new version if it's worth it.

Try Markedfile for your team · Read the API docs