There’s no way to stop someone copying a picture of your signature (or any image) but there are some tricks to stop the image being misused.
Thanks to Office Watch reader, Tim P. for the excellent question:
“I liked your article on inserting signatures. In relation to inserting a picture of my signature, I was wondering whether you could cover whether there is anyway to stop that picture from being copied by others for their own use?”
Only important documents
Limit use of your signature image to documents that really need it — like a contract or agreement.
Be careful who you share the image with. It’s NOT a good idea to add your signature picture to the bottom of emails.
For other purposes (where a signature is a personal or design choice – not essential) use a variation on your normal signature (see below) or use a script font.
Different online signature
Use a different version of your signature for the online use. If someone does copy your signature image you’ll know it was a copy, not your real ink signature.
The obvious thing is to make the signature image a different look/style to your usual signature, perhaps less script and more like block lettering?
Or change the wording of the signature picture. For example, sign online as ‘D Bloodnock’ instead of a usual signing ‘Dennis Bloodnock’.
Add/drop a middle initial.
Add ‘Mrs/Ms/Mr’ to the digital signature, in addition to other tricks.
Remember that extras to your normal signature could be cropped out.
Add a ‘Watermark’ over the signature which makes it harder to copy. Even this isn’t perfect because someone could use an image editor to remove the non-signature/watermark elements.