Blog
Dated posts: the monthly Article 50 enforcement watch, our own conformance application as it happens, what survives upload to each platform, and what changed in the rules.
One of eleven: which inference platforms mark AI output
We read the terms of eleven platforms hosting open-weight models. One attaches Content Credentials, signed as itself; all put output on the customer.
Open-source C2PA signing: SignUnder's code is on GitHub
Since 20 October 2026 SignUnder's signing service is open source under Apache-2.0: the API, the C2PA signer, the watermark worker and the rule packs.
What the C2PA conformance forms actually ask
We are applying to the C2PA Conformance Program. Every field on the first form, what the intake form wants, and the security document's six objectives.