How to prove your photo existed before AI scraped it (without a lawyer)

If you've ever posted a photo online, you've probably wondered: what stops an AI training set from scraping it, then a year from now someone claims your photo is the AI-generated one?

This isn't paranoid. It's the next phase of a problem that already happened to musicians (sample disputes), writers (plagiarism), and illustrators (style mimicking). Photographers are now the cohort getting the most heat — major AI image generators have been sued over millions of scraped images, and every working photographer has a "is that mine?" story brewing.

The standard answer is EXIF metadata + your RAW files + cloud backups. That's three plates spinning, all of which can be edited, deleted, or lost. None of them produce evidence a third party would treat as definitive.

This post walks through the better answer: cryptographic timestamping — a way to lock today's date to a file's contents such that the only path to forge the claim is to re-mine the entire Bitcoin blockchain. Which nobody will do for your wedding shoot.

The fundamental tool: OpenTimestamps

OpenTimestamps is a free, open protocol that works like this:

You compute the SHA-256 hash of your file. (32 bytes; reveals

nothing about the photo.)

You submit the hash to one of ~5 "calendar servers."
Each calendar batches many users' hashes into a single Merkle

root and writes that root into a Bitcoin transaction (approximately once per hour).

You receive a small .ots proof file. The proof says:

"this hash is provably included in Bitcoin block N, mined at time T."

Verification is the inverse: given your original file + the .ots proof, anyone with a Bitcoin node (or just the public chain) can confirm that the hash existed at time T. No trust in any server is required at verification time.

This is the gold standard for proof-of-existence. It's free, it's permissionless, and it doesn't go away if any single company disappears.

The catch with raw OpenTimestamps

OpenTimestamps is a brilliant protocol, but it's a CLI:

pip install opentimestamps-client
ots stamp photo.jpg
# ... wait ~1 hour for the BTC calendar to publish the block ...
ots upgrade photo.jpg.ots
ots verify photo.jpg.ots

If you live in pip install, you're done — go use it, and skip the rest of this post. (Seriously. Stop reading and go run it.)

For everyone else: the CLI is a wall. You need Python, a working build chain for python-bitcoinlib, comfort with the terminal, and the discipline to safely store .ots files alongside your raw photos. Most photographers won't do any of that. So most photos go unanchored, and the AI-vs-real disputes happen with no usable evidence on either side.

A simpler path: drop the file in a browser

There's a small product called Orphograph (disclosure: I built it) that wraps OpenTimestamps with a browser-based workflow:

Open the site, drag your file onto the drop zone.
The hash is computed locally in your browser using WebCrypto.

The image bytes never reach our server.

You get a receipt — JSON file + 5 OpenTimestamps proofs —

downloadable as a single bundle.

The block-pinning upgrade happens automatically server-side

over the following hour; the receipt updates from "pending" to "block-pinned at block N."

You can verify the receipt later with a ~100-line Python verifier — no Orphograph dependency. The receipt outlives our company by design.

Three pricing tiers: free (3 anchors/24h), $19 Writer Pack (10 anchors, never expires, claim code by email), $9/mo Standing Order (unlimited).

How to actually do this for your portfolio

Pick the approach that matches your comfort level.

Path A — free, technical (use OpenTimestamps directly)

pip install opentimestamps-client
# anchor:
ots stamp my_photo.jpg
# returns my_photo.jpg.ots — save it next to the photo
# upgrade after 1 hour to get the BTC merkle proof:
ots upgrade my_photo.jpg.ots
# verify any time:
ots verify my_photo.jpg.ots

Cost: $0. Time: 5 minutes per photo plus 1 hour wait. Defensibility: strongest. You're using the protocol directly.

Path B — free, browser (drag-and-drop monthly)

Visit orphograph.com, drop your best photo of the month into the box. Save the receipt JSON. Done.

Cost: $0/month forever for the first anchor. Time: 10 seconds. Defensibility: same as Path A, with a slight UX trade — the receipt has to be re-downloaded if your browser clears localStorage. Save the receipt to your normal cloud storage or photo backup.

Path C — $19 for a batch (when you have 10 photos at once)

Same as Path B but pay $19 and skip the rate limit. The claim code is delivered by email and lets you anchor 10 files in one sitting. The Stripe receipt is your invoice; the email gets the claim code.

Defensibility: identical to A/B (same OTS proofs).

Path D — $9/mo (you anchor 50+ files per month)

If you batch-anchor a wedding shoot or a fashion week catalog, the Standing Order tier is the only one with unlimited anchors and email delivery. It also gives you an account dashboard showing your history — useful if you ever need to produce a chronologically-ordered list of "what I anchored when."

What this does NOT do

Be honest about the limits, because the AI disputes are going to get litigated and you want to know what your receipts will and won't prove.

A timestamped hash proves:

A specific byte sequence existed at time T. ✅

A timestamped hash does NOT prove:

That you authored it. (Anyone with the file can anchor it.

If you publicly publish a photo, the AI could anchor it the same day you did.)

That the file was made by a camera versus generated.
That the file is legally authentic under eIDAS or any

national qualified-trust-service-provider framework. For that, you need a notary, a qualified TSA, or both.

The right framing is: anchor immediately at capture time, when the only person who has the file is you. That's the temporal moat the AI can't compete with — they need to scrape the file first, and you've already locked the timestamp before they have access.

In practice this means: anchor RAW files before posting JPEGs. Anchor on the camera's SD-card directly if you can. Don't wait until after a viral upload.

What to do this week

If you're a working photographer, here's the minimum-effort path:

Pick your most distinctive image from the last week — the one

you'd most regret losing the "I shot this" argument over.

Anchor it. Free, takes 10 seconds.
Save the receipt JSON to wherever you keep your photo backups.
If anyone ever disputes the date — show them the receipt and

the open-source verifier link. Let the math speak.