Google’s December 2025 core update: why some news sites are seeing sharp Discover swings

If you publish news content, the past couple of weeks will probably feel familiar: a steady drumbeat of ranking turbulence, unpredictable spikes and drops, and that nagging sense that what’s happening in one Google surface isn’t staying neatly contained there.

That theme is front and centre in a 19 December post from SEO consultant Glenn Gabe, who has been sharing running “Core Update Notes” during the rollout. In his update, Gabe says he’s seeing “a number of news publishers with heavy impact” and that several publishers have reached out to him directly to describe volatility across multiple Google surfaces, including Discover, Google News, Top Stories, and the News tab in Search.

A key tension: “minimal overlap with Search”… but is that what publishers are experiencing?

One line in Gabe’s post will particularly resonate with anyone who relies on Discover for distribution. He flags that the Discover impact is “interesting” in light of what Google had “explained recently” about “minimal overlap with Search”, adding that he’s not sure that’s “always the case” based on what he’s seeing. He also notes that some publishers have effectively been “nuked from Discover” during this update.

That “minimal overlap” phrasing aligns with reporting earlier in December around Google Discover’s relationship to Search ranking systems. Search Engine Roundtable covered a Google Search Central Live event in Zurich where a slide referenced “minimal alignment to Search ranking”, with additional discussion about how Discover can surface content from smaller publishers that may not rank strongly in traditional Search.

Put simply: Google has signalled that Discover isn’t just a mirror of the Search results page. Yet Gabe’s field observations suggest that, during this core update at least, publishers are experiencing movement that appears to cut across surfaces in a way that feels linked.

Where this sits in the wider update timeline

Google announced the December 2025 core update on 11 December and later confirmed the rollout was complete on 29 December, taking a little over 18 days. Gabe’s 19 December note lands right in the middle of that rollout window — the period where sites often see the sharpest swings, and where early “winners” and “losers” can still change position as the update continues to settle.

Gabe himself makes that point: he stresses that “anything can change as the update continues to roll out”, and says he’ll share more findings as he continues analysing the data, alongside screenshots of publisher visibility patterns.

Why this matters (especially for publishers)

For publishers, the practical risk here isn’t just a few ranking positions moving around. It’s the possibility that distribution channels you treat as “separate” in strategy meetings — Search, Top Stories, Google News, Discover — can all wobble at once, making it harder to diagnose cause and effect.

Discover is particularly tricky because it’s not driven by explicit query demand in the same way as Search. That makes day-to-day forecasting difficult even in calm periods; in a core update, sudden reductions can feel like someone has turned off a tap rather than gradually dialling down traffic.

Gabe’s wording also hints at a broader point: while core updates are officially framed around improving relevance and satisfaction for users, the lived reality for publishers is that visibility can change dramatically without a single “penalty” message or one obvious technical issue to fix.

What publishers should do next (without chasing ghosts)

Core updates tempt teams into frantic activity. Rewriting headlines, pruning sections, tweaking internal links, often before there’s a clear pattern. A more measured approach tends to be more useful:

• Track each surface separately. Don’t rely on one blended traffic line. Break out Discover, Google News, Top Stories and Search where you can, so you’re not guessing which channel moved.

• Annotate your data with the rollout window. Gabe’s point that things can change during rollout is important. Compare like-for-like timeframes and watch whether drops stabilise after completion.

• Audit content quality at the section level. If certain news categories or templates are disproportionately affected, that’s a clue worth following. Focus on consistency, clarity, and whether pages genuinely satisfy the user intent they attract.

• Be cautious about assuming Discover is “independent”. Google has discussed minimal alignment, but multiple sources and real-world monitoring suggest cross-surface volatility can happen during core updates. Treat Discover optimisation as complementary to (not separate from) your broader quality signals.

The most important takeaway from Gabe’s 19 December note is not a single prediction about where the update will land. It’s the reminder that, for news publishers, core updates can play out across Google’s ecosystem, and that Discover may be more exposed to those tremors than many teams would like to believe.