FEATURES · PROOF
Proof anyone can check.
The certificate of completion on the last page of every signed PDF lists who signed and when. The whole file is sealed, so a later change shows, and anyone can verify a copy with no account.
Sealed PDF · Certificate of completion · Verify with no account
What a sealed copy carries
Four things travel with the file.
The seal
A digital seal over the whole PDF, so any later change shows.
The fingerprint
A SHA-256 hash of the document, printed on the certificate.
The record
Each action with its time, address and browser, kept with the document.
The signers
Each person's name, email and role, and the wording they agreed to.
The file
Five layers, one sealed file.
The page, the fields, the signatures, the seal and the certificate are one PDF. Change any layer and the seal no longer matches.
- PageThe document as it was sent
- FieldsEach box, placed where it belongs
- SignaturesTyped or drawn, with the time
- SealA digital seal over the whole file
- CertificateWho signed, when, and the hash
What is recorded
Every step, with its time. Every signature, with its hash.
- Sent09:14
- Opened09:17
- Signed09:20 · hash c093
- Sealed09:58 · hash 9f2c
What the certificate shows, and how to check it.
- WhoEach person's name, email and role
- WhenThe time of each action, local and UTC
- FromThe address and browser of each action
- AgreedThe exact wording they agreed to
- FingerprintA hash of the document, so a change shows
- DropA signed PDF onto the verify page
- CheckThe seal is valid and the file is unchanged
- ReadWho signed, and when
- PrivateThe check runs in your browser; the file is not uploaded
SAMPLE RESULT: SEAL VALID · NOT CHANGED SINCE SEALING.
Try it
Change one letter and the chain breaks.
In the signature record, each hash covers its own text and the hash before it. Edit any record below and watch every later record stop matching.
…………What a Docustay signature is, and what it is not.
- KindA simple electronic signature with a strong record and a digital seal
- RecordIntent, consent, who, when, from where, and the file's hash
- SealA digital signature over the whole file, with a trusted timestamp when the time service answers
- QualifiedNot a qualified electronic signature
- IdentityNo identity documents or knowledge checks
- AdviceNo legal advice and no promise about any outcome
THE FULL WORDING IS ON THE LEGAL VALIDITY PAGE.
The last page
The last page tells the whole story.
It lists who signed, when, and a hash of the file, on the PDF itself. It does not need Docustay to be read.
- Who and when
- Each person's name and the time of each signature.
- The fingerprint
- A hash of the document, so a later change shows.
Certificate of completion
Document Services Agreement
Signed by Dana Whitfield · 14:02 UTC
Signed by Ada Lovelace · 14:09 UTC
File hash sha-256 9f2c…41ab
SIGNEDThe record
Every step is a row you can export.
Sent, opened, signed, sealed: each is written down with its time, and the whole log downloads as a CSV.
- Same names
- The events are the ones webhooks send, so your system and the record agree.
documents.document.sentAda · key crm-sync
documents.document.openedDana Whitfield
documents.document.signedDana Whitfield
documents.document.executedsealed · 9f2c…41ab
Check it yourself
You do not have to take our word for it.
Drop a signed PDF on the verify page. It checks the seal in your browser, with no account, and says whether the file is intact, whether it carries a trusted timestamp, and what its fingerprint is. Who signed and when is on the certificate page inside the file.
The seal is a digital signature over the whole file. If anyone changes the file afterwards, it no longer matches.
- Verify page: /verify
- How the seal works: /trust#proof
The verifier
Three checks, and what they do not prove.
The verify page re-reads the signature inside the PDF. A forger who only copies the right digest into a fake signature fails the second check.
On the last page
What the certificate can show, and what you can leave off.
| Part | What is printed | Owner setting |
|---|---|---|
| Timeline | Each step in time order: sent, opened, reminded, agreed to sign, signed, completed. | On or off |
| Network address | The address each signer opened and signed from. | On or off |
| Device and browser | The device each signer used. | On or off |
| Document fingerprints | A hash of the original file. | On or off |
| Consent record | That each person agreed to sign electronically: the version, time, address and device. | On or off |
| Closing statement | A sentence at the bottom saying the document was sealed with a digital signature when the last party signed. | Editable, up to 600 characters |
Also on it when they apply: the reason a person gave, who a seat was passed on from, what each signer paid with Stripe's reference, and a signature ID. The certificate is the last pages of the PDF, or a second sealed PDF if you switch that setting.
Keep the record
Evidence you can hand to someone else.
The evidence package
Once a document is executed, a team member can download one zip: original.pdf, signed.pdf, audit-log.csv, evidence.json and a README. evidence.json lists every signature with its hashes and every file with its SHA-256.
A signature ID
The first 12 characters of a signature record's own hash, in three groups of four, printed beside the signature when the owner turns it on. Anyone can recompute it from the record.
How long it is kept
Signed documents stay in your workspace, and you can download the sealed copy and its audit log at any time.
Fetch it
Download the sealed copy from your own code.
curl https://docustay.app/api/v1/documents/$DOCUSTAY_DOCUMENT_ID/signed.pdf \
-H "Authorization: Bearer $DOCUSTAY_API_KEY" -o signed.pdfUntil the sealed copy exists the call answers 404 saying it is being made. Ask again after a moment, or wait for the documents.document.executed webhook.
Self-hosting
On your own server, the seal is yours.
A self-hosted install makes a signing certificate for itself at first run. Set your own to use one from a trusted authority, and point it at a timestamp authority so finished documents carry a trusted timestamp.
A Docustay signature is a simple electronic signature with a strong record and a digital seal. There are no qualified signatures, no identity checks and no legal advice.
Related
Keep going with the next piece.
Questions
Quick answers.
What if the time service is down?
The file is still sealed, and the certificate says the timestamp was not added. We never claim a timestamp we do not have.
Can I download the sealed copy again?
Yes. It is stored with the audit trail, and everyone who signed was emailed a copy.
Will every PDF viewer show the seal as valid?
Some viewers show validity as unknown until they are told to trust our sealing certificate. The verify page is the supported way to check a file.