Hi Adam,
So, when you do that /members route query
https://0-api-crossref-org.libus.csd.mu.edu/members?query=springer
you’ll want to grab the member ID value from the relevant record.
In your case, you’re looking for the third record in that results list, Springer Science and Business Media LLC. And you’ll find that their member ID is 297.
Then, you can query for all the works currently associated with that member and facet by ISSN like this
https://0-api-crossref-org.libus.csd.mu.edu/members/297/works?facet=issn:*&rows=0
That gives you a list of all the ISSNs for journals wherein Springer is identified as the steward of at least some of their DOIs.
That does not mean that Springer is the current publisher or registrant for that journal. It’s not uncommon for a prior publisher to retain stewardship over some of the backfile content while a new/current publisher registers current content.
Then, if you take one of those ISSNs and query for it in the /journals route of the API, the current publisher is listed in that record.
For example https://0-api-crossref-org.libus.csd.mu.edu/journals/0884-8734 gives you
“publisher”: “Springer-Verlag”,
That said, the /journals route isn’t always consistent. (this is a known issue) So, you’re bound to get a lot of ‘resource not found’ responses if you run that /journals/{issn} query for every ISSN.
The workaround to that is to take the ISSN and query for its most recently registered items. Whoever registered the most recent DOI is almost certainly the current publisher.
For example, the first ISSN in that facet list is 0302-9743, so if you run this query, you’ll get the 20 most recently registered DOIs for that journal along with the member ID and the date they were registered:
https://0-api-crossref-org.libus.csd.mu.edu/works?filter=issn:03029743&select=DOI,member,created&sort=created
Since those all say “member”: “297”, you can be pretty confident that Springer is the current publisher.
If you want a more definitive result, you can see who we have in our records as the current publisher with permissions to register new DOIs for each journal by either searching the Title List or downloading the title list csv file. The browsable Title List is updated daily, and the csv file is updated weekly.
Please let me know if you have any other questions.
Best,
Shayn