GoogleAlgorithmConfirmed
Site diversity change
Google limited how many results from the same domain could appear in the top results, generally to two per query.
What changed
Google announced a change intended to increase the diversity of domains shown for a query, typically capping a single site at two listings in the top results. Subdomains were usually treated as part of the parent domain, though Google said they could be treated separately when it made sense. The change did not apply to all queries and left features such as top stories outside its scope.
Timing
Rollout began 6 June 2019. No completion date was announced. Rankings typically remain unstable for the whole rollout window, so measurements taken inside it are not a reliable read on the outcome.