Google has a permanent demotion applied to a site I've run since 1996: http://onlineslangdictionary.com/ . I estimate that my traffic would be 2.5x - 3x what it is now, were the demotion not in place.
These demotions are hidden, permanent, and cannot be appealed. Moreover, these demotions can be performed by hand internally within Google - for whatever reason they choose, or for no reason at all. That is to say, some demotions are manual and not automated.
I have never been officially notified that the demotion exists, in any of Google's available tools or any other way. However, a Google employee checked the internal status of my website and there is, indeed, a permanent demotion in place.
There is no reason for my site to be demoted. This demotion was put in place while Matt Cutts was the head of the web spam team. I asked him about it here on HN, and he lied about it. (I know he lied because of my communication with the Google employee.) You can read my thread with Matt here: https://news.ycombinator.com/item?id=5408087 .
I'd like to make the email chain between the Google employee and I public. But I don't want to ruin someone's career / life, just because they did the right thing and told me about the penalty.
So... I don't know what to do. Thoughts?