Opportunities › Document signing and verification without platform lock-in › Proposed app
Sealmark
Sign documents and releases; anyone can verify them free, with no account.
- Score
- 54
- confidence 53
- Evidence
- 7
- items on the page
- Rivals
- 3
- named in sources
- First version
- 45 d
- estimate
- Type
- Desktop app
- PWA: runs in the browser, installs on Mac and Windows
- Market since
- 2003
- Mature market · AI estimate
ScreensConcept
Desktop app: Signers work with documents and legal releases at a desk, often handling multiple parties and reviewing contracts with careful attention. Sample screens on a computer, in the proposed brand. Their numbers are sample data.
New signing
Draft3 signers
- File
About this appAI proposal
Sealmark lets you sign documents and build releases with open standards, then lets anyone verify them for free. Signers and verifiers need no shared account, no subscription and no vendor's trust list.
Each signature is anchored in public, vendor-neutral records such as a transparency log. A recipient opens a link or drops the file into the verifier, and sees who signed, when, and whether it changed. Standard tools can check the same signature.
It is for small companies, individuals and software teams who sign contracts, issue documents or ship artifacts, and are tired of paying for a service just so others can trust their files.
- Tagline
- Sign anywhere. Anyone can check it, free.
- Voice
- plaintrustworthyopencalm
- Why this name
- A plain word for the mark a signer leaves on a document: it can be checked by anyone, which is the point of the product.
In the first version
Members say which features they would use. It tells PWAS what people want; it changes no score.
Free verification for anyone
Drop a file or open a link to check signer, time and integrity. No account, no fee, no matching platform.
No member yet
Open-standard signatures
Signatures can also be checked with standard tools, so you are never locked in to this app.
No member yet
Public transparency record
Each signature is logged in public infrastructure, so anyone can see it existed at a given time.
No member yet
Multi-party signing by link
Send a document to several signers. They sign in the browser with email or a key, no install.
No member yet
Brand identityAI proposal
Check the name against trademark registers before using it.
Palette
#12372AInk Green · primary#F6F3EAPaper · surface#1E2421Charcoal · text#D9531ESeal Orange · accent#5E8C61Moss · data / verified#D8D2C0Stone · border
Typography
Aa
Sealmark
PricingAI proposal
DocuSign's verified pricing page lists 3 paid plans from $11 to $45 a month. Team and Pipeline sit just below that range as a starting point to test. Verification stays free.
Open
Free
- Unlimited verification
- Sign up to 10 documents a month
- Public verify links
- Proof bundle export
Team
$9 a month
- Unlimited signing
- Custom domain identity
- Multi-party signing
- Email reminders
Pipeline
$29 a month
- API and CI signing
- Artifact release links
- Higher API limits
- Audit export
What it could be worthEstimate
What a software business making this much sells for today, from real deals. Pick a monthly revenue.
If it makes
Worth about
$194,000
Sale range $132,000 to $263,000
$120,000 a year in revenue
From 87 software businesses listed and sold on Empire Flippers in the last year, revenue vetted by the broker: they sell for about 19× their monthly revenue, most between 13× and 26×.
Measured on profit, the middle deal is 32× monthly net profit: about 2.7 years of profit.
An estimate, not an offer or financial advice. A real price depends on profit, growth, churn, how much of the work is the owner's, and the buyer.
How it would growAI proposal
How the product would reach new customers through its own use, and how the first ones would be found. A plan to test, not a result.
- Built-in loop
- Shared outputs. Every signed document carries a verify link and a small badge. Recipients open the public verifier, see the result, and can sign their reply with the same tool.
- Do they become customers?
- Verifiers pay nothing, so they only see it. Test how many recipients sign something themselves within 30 days of verifying, and whether they upgrade.
- First customers
- Open-source maintainers and small software teams of 2 to 20 people who sign release artifacts and also send contracts to clients.
- Where to reach them
- Hacker News and dev forums: Post a Show HN with a live verifier and a signed sample release that readers can check themselves.
- GitHub Actions marketplace: Publish a signing action that adds a verify link to each release page.
- Freelancer communities: Offer free signing of contracts and ask for feedback on the paid custom domain feature.
- First milestone
- Ten teams sign real releases or contracts weekly, and five of them pay for custom domain or API tiers.
Why people already pay for this
- VerifiedHacker News post received 94 points and 32 comments
- Public claimExisting document signing platforms charge for verification, which should be free
- Public claimVerifiers must use the same platform or be locked into Adobe's ecosystem
- Public claimThe verification part is gated behind paid platforms despite being inherently free to perform
- Public claim
Tech stack
Every proposal builds on the same PWA base, installable from the browser on any phone or computer. Dashed boxes are what this app adds.
- AppNext.js and TypeScript
- PWAManifest and service worker
- UITailwind CSS
- Data and authSupabase Postgres
- PaymentsStripe
- EmailResend
- HostingVercel
- This app · Signing and keysOpen-standard crypto libraries and key management serviceSignatures must follow open formats and keys must be stored safely.
- This app · Transparency logPublic, vendor-neutral signature logAnchors each signature in infrastructure no single vendor controls.
RisksAI inference
- RegulatorySome contracts need qualified or legally recognised e-signatures in certain regions. Open-standard signatures may not meet those rules without extra certificate partners.
- CommercialIf verification and basic signing are free, few users may pay. The paid tiers need to be shown to matter to teams.
- TechnicalAnchoring signatures in public logs and keeping them checkable by standard tools for years is hard to get right.
- PlatformReaders like Adobe's use a trust list. Documents signed here may show as untrusted there, which could put off business users.
- DataPrivate keys and signer identity must be handled safely. A key leak would damage trust in every signature.
Everything marked AI proposal or AI inference was written by a model from the evidence on the opportunity page. The proposed name must be checked against trademark registers before it is used.