Skip to content

docs(sign): document signature placement, field selection and the custom logo #123

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
samuelsl27 wants to merge 3 commits into
base: main
Choose a base branch
from
Open

docs(sign): document signature placement, field selection and the custom logo #123

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
9e1ba33
docs(sign): document signature placement and field selection
samuelsl27 Aug 3, 2026
69c1c8e
docs(sign): document the custom logo and its five placements
samuelsl27 Aug 15, 2026
8391e80
docs(sign): note that device certificates work in every connection mode
samuelsl27 Aug 16, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
57 changes: 55 additions & 2 deletions docs/Functionality/Security/Certificate-Signing.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,7 @@ Digitally sign PDFs with X.509 certificates and validate existing signatures aga
Once configured, users can choose **Server** in the **Certificate source** step to sign with the shared certificate.
</TabItem>
<TabItem value="device" label="This Device (Desktop)">
Sign with a certificate held on your own machine - a USB token or smart card (PKCS#11), or the Windows certificate store. The private key never leaves the device: Stirling PDF asks the token or operating system to perform the signing. This option appears only in the **desktop app** and works on every edition.
Sign with a certificate held on your own machine - a USB token or smart card (PKCS#11), or the Windows certificate store. The private key never leaves the device: Stirling PDF asks the token or operating system to perform the signing. This option appears only in the **desktop app** and works on every edition. It is also independent of what the desktop is connected to: whether you are working offline, signed in to Stirling Cloud, or pointed at your own self-hosted server, the certificate is read and used on your own machine. Only the signed PDF continues through the rest of your workflow.

1. Go to **Certificate Sign** tool
2. Upload PDF
Expand All @@ -107,10 +107,63 @@ Digitally sign PDFs with X.509 certificates and validate existing signatures aga

### Signature Appearance

**Visible:** Appears as a box on a chosen page showing the signer name, signing date, and reason, with an optional logo.
**Visible:** Appears as a box on the page, showing details from your certificate and an optional logo.

**Invisible:** Embedded in PDF metadata only, not visible on the page.

#### Placing the Signature

By default the box goes where it always has, on the page you choose. To put it somewhere specific — a printed signature line on a form, for instance — select **Draw the box on the document** and either drag a rectangle across the page or click one corner and then the opposite one.

The page you draw on becomes the page that gets signed, so the page number updates to match. Press `Esc` to leave placement mode without placing anything.

Text inside the box scales to fit whatever size you draw, so it never spills over the surrounding content.

#### Choosing What the Box Shows

Certificates carry more than a name. Tick the fields you want printed inside the box:

| | |
|--------|--------|
| Signer name | Organisation |
| Organisational unit | Country |
| Email | Issued by |
| Issuer organisation | Serial number |
| Valid from | Valid until |
| Signature algorithm | Signing date |
| Reason | Location |

Fields your certificate doesn't carry are skipped rather than drawn blank, so you can tick a field without checking your keystore first. Ticking nothing shows the signer name, signing date and reason, as before.

#### Using Your Own Logo

The box can carry your organisation's logo instead of the built-in Stirling PDF mark. Upload a **PNG or JPEG** and choose where it sits:

| Position | Result |
|--------|--------|
| Left of the text | Logo in a column down the left, details beside it |
| Right of the text | The same, mirrored |
| Above the text | Logo in a band across the top, details underneath |
| Below the text | Logo in a band across the bottom |
| Behind the text (watermark) | Logo fills the box, faded, with the details drawn on top |

Leave the upload empty and the built-in mark is used, as before.

The image always keeps its proportions, so a logo is never stretched to fill its strip. The details keep a usable share of the box whatever shape the logo is, so a wide banner cannot squeeze out the signer's name. **Behind the text** is the one position where the two overlap: the logo is drawn faded underneath so the details stay readable.

When **Repeat it on every page** is also on, the marks on the other pages carry the same logo, so they match the real signature.
#### Repeating It on Every Page

Long documents are often initialled on every page so a reader can see the whole thing was signed. **Repeat it on every page** does that.

:::caution Only one page is really signed
A PDF signature lives in a single place, so only the page you drew on carries the actual signature. The other pages get a mark that looks the same but is not a signature and will not be reported by a validator.

Each mark links to the signed page, so a reader can click it to reach the signature and check its properties.
:::

This option needs a box to have been drawn first, since there has to be a shape to repeat.

---

## Validating Signatures
Expand Down