Can a PDF Be Edited After Signing?
It depends on the signature. A visible stamp or image is just pixels — easy to move. A real digital signature flags any later edit. Plain "signing" via an image tool changes nothing about editability.
Two kinds of "signed"
- Image / stamp — a picture of your signature; the file is still fully editable
- Digital signature (certificate) — cryptographically binds the file; any change invalidates it
What that means
If you "sign" by dropping an image on the page, anyone can still edit text or move the stamp. Only a certificate-based signature (from Acrobat with a real ID) makes tampering detectable.
What we verified
Our sign tool places a visual stamp on the page — useful to mark "signed by me" but it does not lock the document or prove authenticity. We are explicit about this so users do not mistake a stamp for a legal signature.
Honest note: for a contract that must be tamper-evident, use a certified digital signature (Acrobat or a PKI service). A browser stamp is a convenience, not a seal.
FAQ
Can a PDF be edited after signing?
If signed with an image stamp, yes. A certified digital signature makes edits detectable.
Does a stamp lock the file?
No — an image signature is just pixels; the PDF stays editable.
How do I make it tamper-proof?
Use a certified digital signature from Acrobat or a PKI service, not a browser stamp.