What is this owner’s password I need to access my documents in order to save them

The problem appears to be with the type of device you're using to fill out the form.

I located the official U.S. gov page this form is on:

https://www.uscis.gov/sites/default/files/document/forms/i-9-paper-version.pdf

It is secured, but everything is open except for extracting page content.

Trying it on both my 2022 iPhone SE and Mac Mini, I had no issues at all filling out the form within Safari on the Mac, or opening it in a PDF editor. From the iPhone, though, I couldn't do anything with it. Not even after following their link for what is supposed to be a mobile version of the file.

I have exactly the same problem and go crazy!

I had this issue with 2 different .pdf sources one also was one from the government (Australia).

Every time I save the file it does ask me for the owner password which is definitely non of mine!

I tried it on my phone and the mac (in both cases, I downloaded the file from the original homepage.

The exactly same files on my wife's laptop, downloaded from the same source don't have that problem that a password need to be entered...

In my opinion it's either a setting I don't know, can't find or some sort of bug.

The help function in review is also useless as well as all the forums I looked through...

Can anyone help?

It appears that you accessed a form from the U.S. government that does not allow you to save it. No one here would know who the "owner" is, let alone the correct password. I suggest that you contact the governmental agency that provided you with this forum for further assistance.

You will need help from whoever sent that document to you.