Sign AI content under your own name
Article 50(2) requires AI-generated images, audio, video and text to be machine-readably marked. Most inference platforms do not mark at all, and the one that does signs in its own name, not yours. Signunder marks every output, signs it under your certificate, and gives you a public page that proves it.
- 2 Dec 2026
- Marking grace ends for AI systems already on the market
- 1 of 11
- Inference platforms that mark generated output today
- €15M / 3%
- Maximum Article 50 penalty, whichever is higher
verify.yourcompany.signunder.com
Verified- Signed by
- Your Company Ltd
- Certificate
- SSL.com C2PA Level 1
- Created with
- FLUX.1 [dev] via Replicate
- Signed at
- 2026-12-02 09:14:22 UTC
- Watermark
- Present · payload intact
- Altered since signing
- No
Illustrative example. Values are not from a real signed file.
Does your inference platform mark your output?
We checked eleven platforms that host open-weight image, video and audio models. One attaches content credentials, and it signs them in its own name. The rest attach nothing, and most of their terms make the obligation yours.
| Platform | Marks output | Notes |
|---|---|---|
| fal.ai | Yes — in its own name | |
| Replicate | No | |
| Together | No | |
| Runware | No | |
| Baseten | No | |
| Modal | No | |
| Fireworks | No | |
| Hugging Face Inference | No | |
| Novita | No | |
| DeepInfra | No | |
| Wavespeed | No |
Read from each platform’s own documentation and terms on 8 October 2026. Platforms change; tell us if you find this out of date.
How it works
Four steps, and the only one you implement is the first.
- 01
Send us the output
One API call, or point your existing fal, Replicate or Together client at our proxy and change no code at all. Any content credentials the model already attached are kept as ingredients, never stripped.
- 02
We mark it three ways
A C2PA manifest signed under your certificate, an invisible watermark where the model added none, and a perceptual fingerprint. Platforms that strip metadata on upload cannot strip all three.
- 03
Signed with your key, in your name
Your signing key lives in a hardware-backed KMS and is never exported. The certificate names your company, so verifiers show your name rather than a vendor’s.
- 04
Anyone can check it
A public verification page and JSON endpoint on your own subdomain answer whether a file came from you, when, with what, and whether it has been altered since.
What you cannot get anywhere else
Hosted signing services sign as themselves. Certificate authorities sell you a certificate but not the conformance it depends on. Nobody maintains the rules for you.
Own-name signing
Signing under a vendor’s certificate shows the vendor’s name. We take you through C2PA conformance under your own legal name — no application fee, a median of 17 days — and request your free Level 1 certificate.
Maintained rule packs
The EU AI Act and Code of Practice, California SB 942 and AB 853, China, South Korea, India, New York, plus the platform labelling policies. Versioned with effective dates, so every output records which rules applied.
Your own detection endpoint
From 2 February 2027, Code of Practice signatories owe a public detection mechanism. Yours answers “is this one of ours?” for every output you have ever produced.
The dates that matter
Marking is already law. What changes on 2 December is that the transition period for existing systems runs out.
- 2 Aug 2026In force
Article 50 applies
Transparency obligations in force across the EU. Penalties up to €15M or 3% of worldwide turnover, whichever is higher, and lower for SMEs. The Digital Omnibus deferred other parts of the AI Act and left Article 50 untouched.
- 20 Jul 2026In force
Guidelines confirm who is liable
A company integrating a model by API into its own user-facing product is the provider of an AI system, and answerable under 50(2) for what that system generates.
- 2 Dec 2026Upcoming
The grace period ends
Systems already on the market before 2 August 2026 must be marking their output by this date. There is no further relief after it.
- 2 Feb 2027Upcoming
Interoperable detection due
Signatories to the Code of Practice owe a public detection mechanism for the content they generate.
Signunder is not a law firm and this is not legal advice. Each entry links to its primary source in our frequently asked questions.
Be marking by 2 December
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