Gary Illyes from Google confirmed that Google has “suddenly” dedindexed a “vast amount of URLs” from the Google Search index this past February. He said this was done because Google’s “perception of the site has changed.”

Gary said this at the SERP Conf back in mid-April.

Gary said on stage at the 10:40 mark into the interview, “Since February, where suddenly we just decided that
we are de-indexing a vast amount of URLs on a site just because the perception, or our perception of the site has changed.”

Here is the video embed:

Here is the full transcript:

Yes, back in February we had number of unconfirmed Google search ranking updates where tons of SEOs were complaining about seeing their pages drop out of the Google Search index.

Keep in mind, Gary is not saying you will get the “crawled but not indexed” errors because Google your site is considered low quality, it most likely is a technical issue with your site. But if you saw a spike of these “crawled but not indexed ” notices in Search Console in February, it might be related to site quality issues with your site.

We covered a bunch of other topics from Gary at this event a while back including:

Google: We Need Very Few Links To Rank Pages; Links Are Less Important
Google: We Have Taken Action On Some Parasite SEO In Recent Update
Google: We Won’t Change The 301 Redirect Signals For Ranking & SEO

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