It’s not that far-fetched, PDFs in my opinion are closer to vector graphics than to document formats like odt and docx. They have no understanding of format if not using advanced features, like a table in a PDF is just spaced text with lines between them, and text is just independently placed letters. In fact the space symbol doesn’t exist in most PDFs, it’s just that two letters were spaced further apart. So they basically are multiple canvases that are being painted on with letters, lines, fill areas and even bitmap graphics.

Modern PDF actually does further in the direction of a document format by providing the content in a structured way, mostly for accessibility, but also for making the format suitable for automatic processing the contained data.

Which he can borrow cash against

They’ll just use the opportunity to buy back stock.

They aren’t really designed to stop people from breaking in but rather to stop intrusive people that you talk to first before deciding to not let them in. With the chain, you can open the door a bit without allowing the person outside to force himself in without too much force, e.g. by blocking the door with your foot as the door can only be opened fully after closing it.

Advanced versions exist where if you put strain on the chain (mostly trying to push the door open from the outside) an alarm goes off.

Why would you install that door chain thing like that, it makes no sense