Why is -30- or -#- or XXX put at the end of a press release?

Answer 1

They are editing marks. When they go to the editor for final approval. These marking are mark of approval from the proofreaders and the editing staff.

Answer 2

Telegraphers (telegraph operators) were supposed to have signed off a transmission with "30," at least that's the story my journalism professors and old hands in the newsroom told.

As to other end marks it seems reasonable to assume these were just local adaptations.

In the days when the most sophisticated piece of writing equipment in the newsroom was a manual typewriter, stories were written in "takes" -- sometimes half sheets of paper. This was especially the case for handling a breaking news story. The short takes could be churned out and sent to the desk for editing.

To indicate that a particular take was not the final piece of the story, the reporter added "- more -" or some variant of that to the end.

Each take was numbered in succession with a slug line, "Train derailment - 3 - 3"

The last take was signed with the " - 30 -" mark or some variant.

-30-

Answer 3

It's traditional to put XXX at the end of a press release to let the media (and whoever) know that's officially the end of your press release. It probably helped, at one time, prevent someone missing a page and not knowing it.

I've never heard of using -30- or #.

Answer 4

I was taught in journalism class that those are the typical means of ending a press release or statement.

Fortunately, I was told about all of those methods you mentioned (-30- has only been introduced roughly in relatively recent times).