Signing PDFs for Construction: What Actually Counts as a Signature

Every project team eventually asks the same question: is a signature drawn on a PDF actually a signature? The short answer is "usually yes, and sometimes no." The long answer depends on your jurisdiction, the document, and the tool that produced the signature.

Three kinds of signatures

Not every mark on a PDF carries the same weight.

Drawn or typed signatures

A signature drawn with a mouse or trackpad, or typed as text in a signature font, is an electronic signature. Under most modern laws — the U.S. ESIGN Act, the EU eIDAS regulation, and comparable statutes elsewhere — this is legally binding for the vast majority of construction paperwork.

Digital signatures

A digital signature is cryptographically bound to the document and the signer. Any change to the file after signing invalidates the signature. This is what most authorities-having-jurisdiction want on stamped drawings.

Wet-ink scans

A photograph or scan of a wet-ink signature is still an electronic signature — the law does not care whether the pixels came from a scanner or a stylus.

What you actually need

For internal approvals, transmittals, and non-regulated documents, a drawn signature is almost always enough. For anything that will be recorded, permitted, or stamped, check with your local jurisdiction before you sign.

The Sign PDF tool is designed for the first category: fast, browser-based drawing and placement, with the finished PDF never leaving your device.