Skip to main content
Encypher Logo

Text content provenance

Encypher hides a signed label in the text itself, in characters readers never see. Copy a paragraph and the label goes with it. Anyone can check who published it and whether a word changed.

Start signing freeCheck some text
Readers see only the words of a paragraph: The town pool opens Monday at noon. Lifeguards are on duty until 6 p.m. A faint gold stitch under the lines stands for the signed label carried unseen inside the words. A checker reads it back: signed by Town Daily, made with AI: no, unchanged since signing.
The signed label travels inside the words without changing how they look. Anyone can check who signed, what they declared about AI, and whether the text changed.
The standard
The C2PA standard for unstructured textC2PA text-provenance standard: The part of the C2PA standard that puts a signed label inside plain text, using invisible Unicode characters., first published in C2PA 2.3C2PA 2.3: The version of the C2PA specification, published January 8, 2026, that added the standard for unstructured text.. Encypher wrote it.
Copy and paste
The label copies with the words.
Per sentence
Encypher can also sign each sentence, so one quote can be checked.
Limits
Retyping, scanning and translating drop the label.

Try it on your own words

Sign a sample, check it, then change one word and check again.

Edit it or paste your own.

What the label will say

Signed by
Encypher demo identity
AI use
No declaration added
Visible change
None. Every word stays.

Signing and the check take a few seconds.

The label copies with the words

The label is made of hidden markersProvenance markers: Encypher's general name for invisible characters that carry a signed label inside text.: characters that screens do not show. Readers and search engines see normal text. When someone copies a paragraph, the markers come along.

Signed text copied into most apps and sites keeps its label; some apps strip the invisible characters and the check then finds no label; editing the words breaks the seal and the check shows the change.
Copy and paste keeps the label in most apps. Some apps strip it, and any edit shows up when the text is checked.

Check one sentence, not just the article

Standard C2PAC2PA: The Coalition for Content Provenance and Authenticity: the group that publishes the open standard for content labels. signs a whole document. Encypher adds sentence-level attributionSentence-level attribution: Checking that one sentence came from a specific signed source unchanged, even when it is quoted on its own., its own layer on top. Each sentence can then be checked alone.

What each layer lets you check.
C2PA, whole documentEncypher, each sentence
Who published itYes, for the whole textYes, for each sentence
Was it changedAny change fails the whole textNames which sentences still match
A quote on its ownNo, the check needs the whole textYes, traced to the article it came from

Guides by kind of text file

Any text file can carry the label in its characters. Markup and code files can also hold it in one comment block, as the C2PA standard allows.

Text, images, audio, video, documents and fonts can all carry a label: in text it rides in the characters, in every other format it sits inside the file.
Text carries the label in its characters. Images, audio, video, documents and fonts carry it inside the file.

Plain text and data: 4 formats

Markup and code: 10 formats

Documents: PDF, Word, EPUB and more

What drops the label

The label is tied to the exact characters. Anything that makes new characters makes new text.

A text mark is kept through copy and paste, wire feeds and scrapers; sometimes lost in social posts and text cleanup; and lost when the text is rewritten or printed.
The mark rides the exact characters. Tools that copy text as-is keep it; retyping or stripping invisible characters loses it.
  • Retyping or rewording the text.
  • Scanning a printout with OCROCR: Optical character recognition: software that turns a picture of text back into characters..
  • Translating it into another language.

Questions

What is the C2PA standard for unstructured text?
It is the part of C2PA that says how to put a signed label into plain text, such as an article or a post. Encypher authored C2PA's standard for unstructured textUnstructured text: Text with no file around it, such as an article body, a post or a chat reply, so there is no container to hold a label., published as Section A.7 in C2PA 2.3 and carried forward as Section A.8 in C2PA 2.4.
Does the label survive copy and paste?
Yes, when the hidden characters are copied with the words, which is what browsers, email and most editors do. Retyping the text, scanning a printout or translating it drops the label.
What does sentence level mean?
Encypher also signs each sentence on its own. A single quoted sentence can then be checked against the article it came from. This layer is Encypher's, not part of C2PA.
Why are there two ways to hide the label?
The default suits web pages, email and apps. A second mode suits office documents, whose editors can rewrite unusual characters. The checker reads both.

For engineers

Show the technical detail

How the label is carried

The C2PA standard for unstructured text (Section A.7 in C2PA 2.3, published January 8, 2026; Section A.8 in C2PA 2.4) encodes the manifest bytes as invisible Unicode characters placed in the text. The hard binding hashes the text with the markers excluded, after Unicode normalization. Read the specification.

Default mark
For web, email and most apps.
Word-safe mark
For documents edited in Microsoft Word. The verifier detects both.
Sentence level
Encypher can sign each sentence. A quote check returns the sentence and its position in the signed article.
Resolver
Sub-document attribution resolves through Encypher's record. The C2PA manifest itself stays document-level.

Keep reading

Create. Mark. Endure.

Sign your first article free. Checking stays free for everyone.

Start signing freeCheck some text