I actually have 2 press photos, both from different news agencies that are now closed. One being from 1951 and the other 1974. I recently got them, but I am curious as to what the chances are of seeing these prints again in the market. These photos do not have the photographers’ names. But they do have public library stamps at the back. Could the negatives for these still be available? Or can I just assume that the press photos I have are the only originals remaining? Is it correct to assume that despite the news agencies that produced these photos are closed, they are still protected by copyright, even if the photos are now outside the USA?

Another question would be cabinet cards (circa 1900). Since there’s no company that does these anymore, is it safe to assume that each cabinet card is unique and it’s likely there won’t be another copy out there?

TIA.