"Publishers actually reuse ISBNs" is a horror which keeps traumatizing new librarians every so often

@phette23 am I about to learn that ISBNs, like SSNs, are not actually unique?

@phette23 @brianfenton SSNs are not unique..?

"Publishers actually reuse ISBNs" is a horror which keeps traumatizing new librarians every so often

"Publishers actually reuse ISBNs" is a horror which keeps traumatizing new librarians every so often

@phette23 I'm not even a librarian but
just from the perspective of someone who designs database schemas sometimes, this is a crime that should land people in the Hague.

Also ISBNs should ideally be a few digits longer.

@phette23

no

no what do you mean by this???

@futurebird @phette23 ISBNs get assigned in blocks to publishers by the national authority. Discount publishers might retire a title and reuse its ISBN so they won't have to buy another block to publish additional titles. You cannot order the older title anyway, they figure, so the ISBN points at one title in print.

And then there's supermarkets and retailers that don't even bother to assign ISBNs and just use EANs. They're not in the book trade: they're selling *stuff*

@meeoo @futurebird @phette23 exactly! I have seen it twice… One was definitely a recordkeeping error in a publication that would’ve been in press in 2020. They did two with the same ISBN and I’m sure it had to do with changing workflows to be remote.

and then a children’s book from the earliest era of ISBNs and a modern book from the same publisher. That was definitely an intentional reuse and so I’m sure that there are a whole bunch from that group. Because it’s ultimately their number.

@meeoo @futurebird @phette23 it’s also one of those issues that are super rare and so not worth our time checking ahead of time. But it’s very important for us to know that these numbers can’t be relied upon to be unique because it affects our system assumptions.

@platypus @futurebird @phette23 I'd say it isn't that rare. But I guess the publishers that really engage in that practice perhaps don't generally publish books that are of interest for library patrons. Because they churn our pretty generic stuff.

Also publishers of romance novels don't necessarily care for ISBNs