July 2021 link spam update
Month-long link spam update that nullified manipulative links, with particular attention to affiliate and sponsored content.
What changed
Google announced a link spam update designed to identify and nullify link spam more broadly across languages, taking a month to roll out. It published accompanying guidance reminding publishers to qualify affiliate links with rel="sponsored" and to mark guest post and sponsored links appropriately. Google framed the effect as devaluing the offending links rather than penalising sites, though sites relying on them lost rankings as a result.
Timing
Rollout began 26 July 2021. Google declared it complete on 24 August 2021, 29 days later. Rankings typically remain unstable for the whole rollout window, so measurements taken inside it are not a reliable read on the outcome.