Certify instead of sign?

[manuschiller]

With the help of origami it was easy to sign a pdf with my cert.
Would it also be possible to certify a pdf instead of signing it?

My aim is this:

[gdelugre]

As far as I remember, a certified document is a signed document that allows a few modifications (basically filling in forms and adding annotations).

I don't think certifying a document would require much effort, however verifying that a document is certified might be more difficult. Do you need both or is having a certify method would be sufficient ?