GoogleSpam UpdateConfirmed
Penguin 3.0
Long-delayed Penguin refresh, the first in more than a year, which let sites that had cleaned up their links recover.
What changed
Penguin 3.0 was primarily a data refresh rather than a new algorithm, and arrived after a gap of about twelve months during which affected sites had no route to recovery. Google said it affected under 1% of US English queries and that the rollout would continue for several weeks. The long wait between refreshes was a major driver of the decision to make Penguin continuous in 2016.
Timing
Rollout began 17 October 2014. 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.