Google acknowledged the suspected update but says there is nothing webmasters can do to fix their sites if they dropped in rankings.
Google has confirmed that they ran a “broad core algorithm update” last week that has impacted the appearance and rankings of some websites in the search results.
Google posted on Twitter that Google does these types of updates “several times per year” and there is nothing a site can do specifically to “fix” their ranking after the core update runs. “Some sites may note drops or gains,” Google explained and said if a page drops, it doesn’t necessarily mean there is something wrong with that page, it is just how Google changed their ranking models that now benefits “pages that were previously under-rewarded.”
Here is Google’s statement on Twitter:
Each day, Google usually releases one or more changes designed to improve our results. Some are focused around specific improvements. Some are broad changes. Last week, we released a broad core algorithm update. We do these routinely several times per year.
...MOREAs with any update, some sites may note drops or gains. There’s nothing wrong with pages that may now perform less well. Instead, it’s that changes to our systems are benefiting pages that were previously under-rewarded.There’s no “fix” for pages that may perform less well other than to remain focused on building great content. Over time, it may be that your content may rise relative to other pages....