An e-signature is simply the electronic equivalent of your original handwritten signature—a way to show that you have approved the contents of a document. “Some people think it’s a digitized signature, but that’s actually kind of dangerous,” explains Tom Gonser, founder and chief strategy officer of DocuSign, a market leader. The most obvious danger: once a signature is stored as a JPEG image, it becomes easy for the wrong person to copy and paste it into a different document.

Digitized signatures pose other problems, too, as Gonser demonstrates with a prank he sometimes pulls: email him a non-disclosure agreement as a PDF file, and he’ll make harmless edits to the document and insert a signature that may or may not look like his real John Hancock. Since most people don’t bother to look over e-mailed agreements for stealthy changes, nor do they typically have the signer’s real signature for comparison, they open themselves to the risk of fraud. That’s why, even more than a decade after the E-Sign Act of 2000laid the legal groundwork for electronic signatures, high-stakes contracts by and large have continued to be signed on paper with an original, “wet” signature.

A New Era for Signatures | News | Communications of the ACM.