Coming soon to theApp Store

Invisible mark

Free

On this page

An invisible mark helps you tell which copy of a document leaked. When you share or save a scan, turn on Add an invisible mark and, if you like, note who it’s for (“Landlord”). Later, Tools → Check a mark looks at a file or a picture and tells you whether it’s one of your marked copies, and which one.

What it is

Paperwise changes the page images very slightly, in a pattern only your own key can make. You can’t see it: on blank paper no dot changes by more than the smallest step of grey. The pattern carries a short id for that one copy.

Check a mark gives one of two answers:

  • Marked by you: “This is the copy of Lease agreement you shared on 30 Oct 2026 (for: Landlord).”
  • No mark of yours found.

Each document keeps a list of its marked copies: More → Marked copies, with the date, the note, how it left (the share sheet, Save to a folder or a share link) and the number of pages.

The mark is made for PDF, JPG and long image copies of scans. Notes, files, cards and Word, Excel or PowerPoint copies can’t carry one.

Step by step

Add a mark

  1. Open the document and tap Share.
  2. Pick PDF, JPG or Long image.
  3. Turn on Add an invisible mark and type who it’s for (optional).
  4. Tap Share, or Save to a folder….

You can also add a mark when you:

  • create a Share link (the switch is on the link sheet);
  • Select several scans, tap Share, then With an invisible mark…: each PDF gets its own mark.

The copy appears in More → Marked copies once the share sheet closes, the folder picker saves it or the link is made. A copy shared through the share sheet is listed even if you closed the sheet without sending it, because iOS doesn’t tell apps whether something was sent: delete it from the list if you didn’t send it.

Mark every copy of a document

  1. Open the document and tap Markup → Watermark.
  2. Tap the Invisible tab at the top. (The Visible tab is the ordinary watermark people can see.)
  3. Turn on Mark every copy of this document.

From then on, Add an invisible mark starts on whenever you share, save or link this document, and Select → Share asks who the copies are for when every document you selected has it on. You can still turn the mark off for one copy (No mark). You can also get there from More → Marked copies → Mark every copy, or from Mark every copy of this document… under the switch in the Share sheet. It syncs and backs up with the document.

Check a file or a picture

  1. Tap Tools, then Check a mark under Check.
  2. Choose Choose a file (a PDF or an image in Files), Choose from Photos (a picture or a screenshot) or Take a photo (of a screen showing the page, held straight).
  3. Read the answer. If the copy is in your list, tap Open the document to go to it.

See or delete marked copies

  1. Open the document and tap More (•••).
  2. Tap Marked copies.
  3. To remove a copy from the list, tap its bin and confirm.

Deleting an entry doesn’t remove the mark from the copy, which is already out there. A later check still says Marked by you, without the details.

Free and Pro

The invisible mark and Check a mark are free.

Privacy

  • Marking and checking happen on your iPhone. Nothing is uploaded to check a file.
  • Your mark key is made on your iPhone and kept in its Keychain. It travels only inside your Sync & Backup and your iCloud backup, encrypted, so your other devices and a restored iPhone can check your marks. We can’t read it.
  • Without your key the pattern is just noise: nobody else, not another Paperwise user and not us, can find, read or fake your mark.
  • The list of marked copies is in Paperwise’s encrypted database, and syncs and backs up with its document.
  • An ID, a medical paper, a bank statement or a tax paper still asks for Face ID before you share it.
  • Documents in a private vault can’t be marked.

Tips

  • Use a note that tells copies apart, such as the person or the agency you sent it to.
  • A screenshot of the page, or a picture saved from a chat app, can be checked too, as long as most of the page is in it.
  • Searchable PDFs keep their text layer unmarked: the mark is in the page images.

What if…

What if the check says “No mark of yours found” on a copy I marked?

The mark may not have survived. It is kept through compression, resizing, cropping that keeps most of the page (about 60 %), screenshots and PDF conversions, but not through printing (or a photo of a printout), a rotated page, or someone removing it on purpose. A copy made before you turned the switch on has no mark.

What if it says “Marked by you” but no details?

The copy carries your mark, but it isn’t in this iPhone’s list: you deleted the entry, or the copy was made on your other device and hasn’t synced yet.

Is the mark proof?

No. It helps you tell which copy leaked. Only your key can check it, so it can’t show anyone else on its own.

Still stuck? Write to support@paperwise.app.