I haven't finished this yet, because it's really long. It concerns 2016's U.S. election, Brexit, and probably some other stuff as well. Some people have claimed the impact of this particular firm has been over-inflated in reporting about it, and I don't really know whether that's accurate, but if this story is all true, it's alarming as hell.
The great British Brexit robbery: how our democracy was hijacked | Technology | The Guardian