I just noticed recently that many of the private blog networks that I have access to have been completely de-indexed. It's the same as what happened in September, 2014. Massive de-indexing all at once and thin content penalties.
What is even more interesting is that it seems Google is taking direct aim at money sites built on expired domains. Out of a collection of roughly 30 different money sites, all were de-indexed except for two of the sites that weren't built on expired domains. In this particular situation, I think that speaks volumes as to what Google is trying to say.
Even though they've been de-indexed, I really don't want to 'out' the group of money sites I'm talking about. However, this isn't the only batch. I've seen enough 'damage' just from what I have access to to believe Google is going through another wave of de-indexing. Look at the SEMrush shots below for just a few of the sites.
I'm not sure exactly when it happened -- I believe sometime during April? I wrote a post on my blog about it. What are your thoughts? Have you had any mass de-indexing recently? What about money sites built on expired domains de-indexed?