Short answer
A visible signature is a mark that people can see on the page. It does not prove who added it or show whether the file changed later.
PDF Tools can place a visible signature. If the receiver requires verified identity or tamper evidence, use the certificate-signing process they approve.
When to use this method
Use a visible signature when the receiving party accepts a placed mark. Use an approved certificate-signing service when identity verification, certificate validation or tamper evidence is required.
What you need before signing a PDF
- The receiver's answer about which signing method they accept
- An unchanged copy of the PDF
- A signature image without unintended personal information, if a visible mark is accepted
A certificate-based signature uses cryptography and a certificate that a PDF reader can validate. A visible signature does not provide that validation.
Choose the signing method before editing
Ask what the receiver requires
Confirm whether a visible mark is accepted or a named certificate standard is required.
You should see: a clear answer before you change the PDF.
Use the appropriate tool
Place a visible signature in PDF Tools only when that form is accepted.
You should see: the signature mark in the page preview.
Review placement
Check page, size, background and nearby text before saving.
You should see: a readable mark that does not cover important content.
Save and reopen the copy
Open the new PDF and check the intended page. Use the receiver's approved process when a certificate is required.
You should see: the mark on the chosen page and the original PDF still unchanged.
What each signature provides
The two methods serve different requirements.
Scroll the table horizontally on a narrow screen.
| Capability | Visible signature | Certificate-based digital signature |
|---|---|---|
| Visible mark on the page | Yes | Often |
| Cryptographic signer identity | No | Yes, subject to certificate validation |
| Tamper evidence after signing | No | Yes, when correctly validated |
| Available in Osenpa PDF Tools | Yes | No |
If a reader reports that a signed PDF changed
Adding a visible mark modifies the PDF. If the source already carried a certificate signature, that modification can affect its validation state. Return to the unchanged source and follow the recipient's approved signing order. Do not describe a placed mark as certificate signing.
Signature mistakes
- Calling an image a certificate signature
- Modifying a document after a separate digital-signing step
- Assuming every recipient accepts the same signing method
Signing checkpoint
- The recipient confirmed the required method.
- After reopening the output, the mark appears on the intended page without covering important text.
- If verified signer identity or tamper evidence is required, use the recipient's approved certificate-signing process because a visible mark does not provide either one.
Osenpa PDF Tools
Add a visible text or image signature only when the recipient accepts that format. It is not certificate signing.