Contracts, creative work, shipping, research, receipts. Any time you need to prove something existed exactly as it was, on a specific date, without trusting anyone to vouch for it.
For work where proof of creation, integrity, or timeline can change the outcome.
Artists, writers, musicians, designers
Problem
Digital work spreads easily, but proving you created it first is hard. SIAE deposits cost money and work per-jurisdiction. Screenshots and "sent-to-self" emails are trivially fakeable.
How BA | Stamp helps
Stamp the file at the moment of creation. The certificate binds the SHA-256 of your work to a blockchain block time — publicly verifiable by anyone, in any country, forever. If someone later claims priority, your certificate settles it.
Typical situations
Engineers, founders, product managers
Problem
When a leak, copycat, or IP dispute surfaces, "we had this first" is only as strong as your ability to prove it. Git history is editable, screenshots don't hold up in court.
How BA | Stamp helps
Stamp a source tarball, design doc, or spec at key milestones. Each hash is anchored on-chain — falsifying the timeline would require rewriting the blockchain. Pair with open-source release tarballs for the strongest chain of evidence.
Typical situations
Civil, structural, mechanical engineers, architects
Problem
Plans, CAD files, inspection reports, and calculation sheets are contested years after the fact. Regulators, insurers, and courts need to know what was approved and when.
How BA | Stamp helps
Stamp the approved revision of every drawing or report. The certificate contains the hash of the exact file that was signed off — later "this wasn't the version we approved" arguments become impossible when the file reproduces the same fingerprint.
Typical situations
PhD students, professors, R&D teams
Problem
Priority disputes over research findings are common — and slow-moving peer review leaves data exposed before publication. Getting scooped is costly; proving you had the result first can be decisive.
How BA | Stamp helps
Stamp raw data, intermediate analyses, and thesis drafts as you produce them. Each hash becomes a public, tamper-proof timestamp — admissible at a tenure hearing, a grant dispute, or a publication priority claim.
Typical situations
Lawyers, notaries, compliance officers
Problem
Contract versions proliferate. NDAs, LOIs, and term sheets get amended in email threads. When a dispute surfaces, reconstructing "which draft did the counterparty see on which date" can be the whole case.
How BA | Stamp helps
Stamp each version the moment it's sent or received. The PDF certificate cites eIDAS Art. 41, Art. 2712 of the Italian Civil Code, FRE 901(b)(9), and equivalent frameworks across 30+ jurisdictions — ready to attach to a filing.
Typical situations
External auditors, accounting firms, internal audit
Problem
Audit evidence needs to be provably unaltered between collection and final report. Regulators and courts ask: was this the actual workbook, export, or ledger extract at the time of the review?
How BA | Stamp helps
Stamp working papers, data exports, and extract files the moment they are produced. The hash on the certificate proves the version that was reviewed is bit-identical to what's later cited.
Typical situations
Reporters, editors, source-protection workflows
Problem
Time-stamping a leaked document protects both the source ("I had this before retaliation") and the reporter ("I had this before publication"). Traditional timestamping requires trusting a centralised service — risky when the story is sensitive.
How BA | Stamp helps
Hashes are computed locally and anchored on public blockchains. No one — including us — can read the content or identify the source from the anchor. The certificate proves the timeline without revealing the document.
Typical situations
For everyday moments where a photo, a receipt, or a screenshot needs to be provably unaltered years later.
Anyone sending something that matters
Problem
Parcel arrives damaged or empty. The shipper claims you never put X inside; you say you did. Couriers' own "contents" tracking doesn't exist — they track the box, not what's in it.
How BA | Stamp helps
Photograph the contents before sealing the envelope or box. Stamp the photo. The certificate proves the exact pixels of that image existed before shipping — when the dispute arrives, you have objective evidence.
Typical situations
Tenants, landlords, buyers, insured parties
Problem
Security deposits disappear over alleged damage that was there on check-in. Insurance claims get denied because the provider disputes when the damage occurred.
How BA | Stamp helps
Walk through the property with your phone, photograph every room, every scratch, every appliance. Stamp the photos at check-in and check-out. The certificate binds the photos to that exact date — no more "this scratch looks suspicious".
Typical situations
Anyone buying something worth protecting
Problem
You need the receipt for a warranty claim three years later — but paper receipts fade, email receipts get lost in archives, and merchants sometimes dispute purchase dates.
How BA | Stamp helps
Scan or photograph important receipts and serial-number labels. Stamp the file. The certificate proves the receipt existed on the purchase date — if you ever need to defend a warranty claim, the merchant can't claim you forged a later one.
Typical situations
Victims of harassment, parties to online disputes
Problem
Harassing messages, threats, defamatory posts get deleted before you can report them. Screenshots can be edited. The platform may not retain them. The burden of proof falls on you.
How BA | Stamp helps
Take the screenshot, stamp it immediately. The certificate proves the image file existed on that specific date — long before the sender deleted it, before the platform archived it, before any retroactive edit. Admissible in civil and criminal proceedings.
Typical situations
Parents, families, personal archivists
Problem
The photo of your child's first steps, the letter from a grandparent, the draft of a family contract — these exist on a phone or hard drive with no verifiable date beyond EXIF metadata (which is trivially editable).
How BA | Stamp helps
Stamp the files when they matter. Decades later, the blockchain anchor still proves the file existed exactly as it is, on exactly that date. No dependency on us, no dependency on any cloud service still being alive.
Typical situations
Our verifier is public on GitHub. Anyone — a judge, a lawyer, a counterparty — can check the certificate without our involvement.
The anchor is on Polygon mainnet, verified source on Polygonscan. Dual-anchored to Bitcoin via OpenTimestamps for long-term gravitas.
The PDF certificate references applicable legal frameworks for your country — from eIDAS 2.0 to Art. 2712 c.c. to FRE 901(b)(9).
A stamp takes 30 seconds and starts at $2.99. The certificate lasts forever.
