Many people "sign" PDFs by pasting a scanned image of their handwritten signature onto the page, and assume this is what electronic signing means. It is not quite that simple. A scanned signature image is one specific, and rather weak, form of electronic signature. Understanding the difference matters the day a document is disputed, because the two do not carry the same evidential weight at all. Here is the distinction in practical terms, and how to choose for each document.
What a scanned signature actually is
A scanned signature is a picture: pixels showing what your handwritten signature looks like. When you paste it into a PDF, the document shows a familiar visual mark, which is why the practice is so widespread, but the file records nothing about who placed the image, when, or whether the document changed afterwards. Three weaknesses follow:
- It is trivially copyable. Anyone who has ever received a document with your scanned signature can extract the image and paste it elsewhere. The mark proves familiarity, not presence.
- It carries no timestamp or identity binding. Nothing technical links the image to you or to the moment of signing.
- It does not protect document integrity. The PDF can be edited after the image was placed, with no trace on the signature itself.
Legally, in most jurisdictions, a scanned signature still counts as a simple electronic signature: courts look at intent and context, not just the mark. Contracts signed this way are not automatically invalid. But when the other side disputes signing, your evidence is the surrounding context (emails, witnesses, conduct), not the signature itself.
What an electronic signature is
An electronic signature, in the proper sense, is a process, not a picture. Signing through a dedicated tool typically records the act of signing as an event: the signature is drawn or applied by the signer in the moment, attached to a specific version of the document, usually with a date. Stronger variants, advanced and qualified signatures under eIDAS, add a cryptographic certificate: the signature is mathematically bound to both the signer and the exact bytes of the document, so any later modification is detectable.
Side by side
| Criteria | Scanned signature image | Electronic signature (process) | Certificate-based signature (AES/QES) |
|---|---|---|---|
| Legal admissibility | Yes, as simple e-signature | Yes, as simple e-signature | Yes, strongest presumption |
| Proves who signed | No | Partly (context, trail) | Yes (certificate) |
| Proves when | No | Usually (date applied) | Yes (timestamp) |
| Detects later edits | No | No | Yes |
| Copy/reuse risk | High | Low | Very low |
| Effort | Low | Low | Higher (certificate needed) |
When a scanned signature is acceptable
Realistically, scanned signatures are everywhere and remain fine for low-stakes, low-dispute-risk documents: internal approvals, routine letters, school forms, acknowledgments, documents exchanged between parties who trust each other and keep an email trail. If you do use one, protect yourself with three habits: send the signed document from your own email address (the trail is your evidence), flatten or password-protect the PDF so casual editing is harder, and never share your signature image file itself.
When to use a real signing process instead
Move up from the pasted image whenever the document creates obligations someone might later deny: client contracts, service agreements, NDAs, offer letters, settlements. Signing through a tool like EasyPDF's sign tool, drawing your signature in the moment and dating it on the final version of the document, produces a cleaner record of intent than a recycled image. For documents with serious litigation or regulatory stakes, use a certificate-based signature through a qualified trust service provider; that is the level where tampering becomes provable.
Frequently asked questions
Is a scanned signature legally binding?
It can be. Most laws treat it as a simple electronic signature and look at intent and context. The practical problem is proof, not validity: the image alone shows nothing about who applied it or when.
Someone pasted my scanned signature without my consent. Is the document valid?
A signature applied without your consent does not express your intent, and forging a signature is an offence in most jurisdictions. Document validity aside, gather evidence (originals, emails, timestamps) and seek legal advice. This risk is precisely why signature image files should never circulate.
Does drawing my signature in a tool beat pasting an image?
For evidential purposes, yes, modestly: the signature is created in the moment for that document and dated, rather than being a reusable file. For strong protection, a certificate-based signature is the real step up.
Should I flatten a PDF after inserting a signature?
Yes. Flattening merges the signature into the page so it cannot be casually selected and copied out, and it fixes the document's appearance. Combined with password protection, it raises the effort needed to misuse the file.