What Are Userproperties?

A PDF can carry extra information fields that whoever made it invented, on top of the standard ones like Title, Author and Creator. Userproperties is the simple yes-or-no flag that tells you whether a document contains any of those extra fields at all.

Which files show it, and where the value comes from

Userproperties belongs to PDF documents. You will not meet it in a photo, a video or an audio file. It is also known as XMP User Properties, after Adobe's Extensible Metadata Platform, the metadata format that PDFs and many other file types use.

The flag itself is set by software, not typed in by hand. It appears when the program that produced the PDF attached its own named properties to the document. Programs that do this are usually carrying structured information across from somewhere else: engineering and CAD exports, document management systems, report and form generators, and publishing templates. The content inside those properties, though, often did start with a person. Someone filled in a project number, a client, a department or a review status in the original application, and the export carried it into the PDF.

What the value looks like

There are only two possible values, and no unit: Yes if the document carries author-defined properties, and No if it does not. Some tools print the same thing as true or false.

That is all this row can tell you. It records that such properties exist somewhere in the document; it does not list their names or their contents. So a Yes is a pointer rather than an answer, and a No is a complete answer: there is nothing of this kind in the file.

Why it matters

The reason to care is privacy, and specifically the kind of information that leaks by accident. Author-defined properties are where internal detail tends to sit, precisely because they were created for internal use and never meant to be read by an outsider. A drawing exported from a design tool can carry a project code and a site name. A contract exported from a document system can carry an internal reference, an approver or a department. None of it shows on the page when you open the PDF and scroll through it, so nobody notices it is there.

A Yes is therefore a good reason to look closer at a file before you publish it, e-mail it to a client or attach it to a public filing. Clearing a PDF's metadata removes these properties along with the rest of the hidden fields, which is the usual fix when a document has to leave the building clean.

There is a second, quieter use. If you are handing a PDF to a printer, a publisher or an archive, the flag is a quick check on what an export actually did. It tells you whether extra structured data came along for the ride, or whether the file is exactly as plain as it looks.