I used to work on a news site and the process to get listed on Google News was very manual, at least compared to how you think the rest of Google operates. You had to have a physical address and phone number (though I don't think the two attributes are actually tested, i.e. sending a postcard via snailmail). You also had to configure your pages for the spider so that if your site delivers wire content (e.g. Reuters, AP) or does aggregation, the spider would ignore those pages, and only pick up your original news. The first time we submitted, the response we got seemed to indicate that someone had looked over our sitemap and saw aggregated news/wire reports, and so we had to resubmit. The process took a few weeks, IIRC.
That said, bigger news sites were probably whitelisted...it seems like the whitelist could be done algorithmically...but the number of new authoritative news sites, in theory, changes so slowly, that there's probably not really a need to do that.
When I worked at CNET, we were (and still are) indexed by Google News despite not having three-digit numbers in URLs.
That's because your excerpt from Google News' guidelines left off a very important addendum: "Please note that this rule is waived with News sitemaps."
Actually the big reason why it may have worked back in the day for CNET was because it was CNET.
Thought these days a news sitemap suffices.
I would personally still add the 3+ digit unique number to the permalinks and eventually if necessary remove it once rankings improve overall on Google News.
Some Back Story
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I consulted for a Movie News and Review website for about 6 years. We had news sitemaps and would show up on Google News once in a while, but one of the small yet significant changes that we made that increased ranking on Google News was when we implemented adding a unique number to urls.
That was implemented back around 2009-2010.
We stopped using that unique numbers in the URL around 2013, mostly because the numbers were becoming pretty darn big. We noticed a small downtrend in Google News traffic which stabilized in a couple of months.
For anyone using Wordpress unique numbers can be added using a permalink structure such as:
/%postname%-%post_id%/
If you do decide to use it don't forget to setup 301 redirects.
which would not fulfill (the basically deprecated) three digit spec for the first 99 posts (maybe even the first 100).
also it makes the URL longer, less user friendly and you have to deal with an URL migration that you might have to revert at some point (i.e.: the example you mentioned)
additionally: as it is mentioned that the 3 digit requirement is "waived" with a google news sitemap it is a strong indicator that this is a crawling, not a ranking directive.
my 2 cents: don't do it, as it would be a clear violation of the golden URL rule a.k.a. "Don't overdo the f###### URLs!"
yeah, and from the paragraph you just cited you left out the last sentence.
"Please note that this rule is waived with News sitemaps."
so basically the >= three digits rule doesn't apply any more (for years now), as a matter of fact i don't know why google still has in in there as it always leads to a lot of confusions.
i once consulted a big newspaper which were in an ongoing project to change their URLs just because one of their (middle)managers has read this spec...
That said, bigger news sites were probably whitelisted...it seems like the whitelist could be done algorithmically...but the number of new authoritative news sites, in theory, changes so slowly, that there's probably not really a need to do that.