It would seem that there is a large search algorithm update that is currently being rolled out by Google that began around Sunday, June 25. According to John Mueller of Google, he said, “We make updates all the time,” when asked about the speculation around a Google update. In the opinion of Barry Schwartz, it seems that “there was an algorithm update to the Google search rankings over the past few days that is still rolling out.”
It wasn’t officially confirmed by google, outside of John Mueller’s normal reply to any question that focuses on algorithm updates. Based on all the chatter across the industry that Schwartz has been tracking, along with all the automated tracking tools from Mozcast, SERPMetrics, Algoroo, Advanced Web Rankings, Accuranker, RankRanger and SEMRush, among other tools,it would appear that there was a real algorithm update done behind the Google curtain.
There are some screen shots of those tracking tools (all from the Source post):