How The Block proves its photography.

Before an image can appear on The Block it passes a layered server-side check: file structure, EXIF, camera-specific MakerNote, internal consistency, a device blocklist, and tamper detection. Phones, action cams and unverifiable files are rejected. The pipeline is fail-closed — when the evidence is ambiguous, the image doesn't get in. There is no human override that waves doubtful files through.

For a picture desk this means the archive is filtered at the source: everything searchable in the Desk cleared the same gate, without exception.

C2PA — the Coalition for Content Provenance and Authenticity — is an open standard, now formalised as ISO/IEC 22144, adopted by camera makers including Leica, which ships it in-camera today. A Content Credential is a cryptographically signed, tamper-evident record inside the file itself: what made it, and what has happened to it since. Its proof doesn't depend on The Block — open a signed file in any C2PA-aware tool and the record holds on its own.

The Block works with the standard in both directions:

• Credentials that arrive are preserved. If a photographer's camera or editor signed the file, The Block never strips it — preservation is verified in our pipeline tests and logged per upload in an audit trail.
• Unsigned work is signed at publish. Professional members opt in to signing when they publish — a cryptographic statement that the file left the platform exactly as published.

This is the part no wire service offers. When your desk licenses an image, the delivered file is re-signed with a new Content Credential recording the licence — deal reference, date, usage class — chained on top of the existing signatures. Nothing beneath is disturbed: the capture record and the publish signature survive intact, and the pixels are untouched.

capture record → publish signature → your licence

The photograph you put on a page carries its own paperwork — checkable by your standards desk, your legal team, or anyone else, years later, without asking us.

Don't take the claim on trust — that would defeat the point:

• Drop any delivered file into contentcredentials.org/verify — the public inspector run by the Content Authenticity Initiative.
• Or use the open-source c2patool in your own pipeline.
• Inside the Desk, every asset page shows its provenance panel and the verify tool re-checks any file you upload back to us.
• Every completed licence also has a permanent public record at theblock.photos/deal/… — so even a copy stripped of its metadata can be traced back to its deal.

Standards references: c2pa.org · contentcredentials.org

A Content Credential proves a signer made specific claims about a file at a specific time — strong, checkable evidence. It is not proof of what the camera was pointed at, and no verification system is a guarantee that no clever attack will ever exist. Two practical caveats worth knowing before you publish:

• Social platforms and some CMSes strip file metadata on upload — a re-posted copy may lose its credential. The permanent deal record on this site is the durable answer: the licence outlives any one copy of the file.
• The Block's publish and licence signatures currently verify as Valid with The Block as the named issuer; our listing on the C2PA public trust list is in progress through the official conformance programme. The cryptography is the same either way — the trust list changes how third-party tools label the issuer, not what is proven.

We would rather you understand exactly what the proof covers than oversell it. That posture is the product.