Prevent spam in fillable PDFs

[jablko]

The problem: Several years ago the small college where I worked stopped using fillable PDFs because of the large amount of spam submissions they were attracting. We went to using PHP forms and that's fine for most people. However, I get calls every once in a while from departments who can't understand why output of web forms can't look EXACTLY like the printed versions/PDFs. The easiest way to silence their complaints would be to start using fillable PDFs again, but we don't want to do that if we start getting inundated with spam submissions again.

The question: Does anyone know a way to prevent spam in fillable PDFs? Captchas, hidden fields ... whatever is available.

 

[Darth.Titan]

Some interesting ideas are here.

 

[angelwatt]

Just to clear this up for myself, are you talking about users filling out PDFs online and putting spam in it, or are you talking about users filling out online forms that get turned into PDF files? I've dealt with protecting online forms, but hadn't heard about any spam in PDF files.

 

[jablko]

I'm talking about bots finding fillable PDFs and filling them out then submitting them. I know how to combat bots on a PHP/ASP/etc form. I want to know how to do it on a PDF which would normally be filled out by someone at home but instead wants to sell me Viagra.