Third-party SERP volatility tools are indicating a potential algorithm update on December 16th coming to visible fruition, which would tie in with the timeline for other previous non-IKS updates.
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Webmasters across the RuNet have also been noticing changes in the search results, some of which look like Yandex testing new things – such as 15 results on the first page instead of the traditional 10:
for many requests, there are a lot of sites on the 1st page (I counted as many as 15)
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Hi, I am also seeing an increase to 15 sites in the search results. And besides, websites which I have never seen, with X 10 … (Moscow region), got to the top. Some strange shake-ups are taking place.
However this test hasn’t been visible for all.
Other Webmasters have noticed changes in websites gaining and losing quality marks, and general changes in the placement of Yandex served products (such as Zen).