Comparison
SynthID vs C2PA Content Credentials for Article 50(2)
Article 50(2) requires generative-AI outputs to be marked in a machine-readable format, so far as technically feasible. Two families dominate practice: invisible watermarks (Google SynthID is the widely cited example) and cryptographic provenance metadata (C2PA Content Credentials). They answer different failure modes; serious pipelines often use both.
Check a file or URL| Google SynthID | Adobe Content Credentials | |
|---|---|---|
| What is actually embedded | An imperceptible signal in pixels, waveforms, or token statistics. The mark is the content. | A cryptographically signed manifest (C2PA) attached as metadata, recording how the asset was made and edited. |
| Survives metadata stripping | Yes, by design — screenshots and re-uploads are the point. | No. CDNs, social platforms, and re-encoding often drop the manifest. Pair with a watermark if that is your distribution path. |
| Who can verify it | Typically the vendor’s detector (SynthID Detector for Google’s mark). Cross-vendor watermark detectability is still immature — the gap the Feb 2027 interoperability milestone targets. | Anyone with a C2PA-aware verifier. Open standard; Content Credentials Verify and c2patool are in this directory. |
| What this site’s checker can see | Nothing. Invisible watermarks are not in the file’s metadata bytes. | C2PA / JUMBF / Content Credentials / IPTC-style strings, when they are still attached. |
| Article 50(2) role | Machine-readable marking that remains after the file is copied as pixels. | Interoperable, inspectable provenance — the closest thing to a lingua franca, when it survives the pipeline. |
Takeaway
If you generate via Google models, SynthID may already be present — verify, don’t strip it. If you need third parties to inspect provenance, add C2PA. If you only run this site’s checker and see no C2PA bytes, you have not ruled out SynthID.
Tools from the catalog
Mapped from public catalog entries and the existing marking guide. Not legal advice. Featured placements, if any, are labeled on tool cards. Get featured.