To be fair, there was no public record of it until 2012 or so.
I'm not sure if reddit publicly acknowledged it before then, but it was certainly known that you were doing it. (It was also pretty damned obvious that you guys were fucking with vote counts -- e.g. "66% like it" on every post -- among other questionable anti-spam tactics...)
The earliest record I can find of the idea being discussed on reddit -- there might be earlier ones, this was just the earliest I've been able to dig up so far -- was in a suggestion by user ltbarcly back in June 2007:
> A better idea is a silent ban. Let him post comments, and show him those comments, but just leave them out for everyone else.
Source, as preserved by archive.org: https://web.archive.org/web/20070604141333/http://reddit.com...
There are also blog posts complaining about it from well before 2012 -- e.g. here's one from 2010: http://www.stochasticgeometry.ie/2010/03/09/silently-banned-...
The comments on it even use the term "shadowbanned".
pretty sure implies he has a hunch that they did, not 100% certainty. They may've said they hadn't considered such a thing before in a "forum" that the OP was able to overhear this either directly or indirectly and it wouldn't be a stretch to consider that in Facebook's history of borrowing from others, they then borrowed it from reddit.
It doesn't discount that it existed prior to reddit, just that they may have been the source for Facebook.
Microsoft was selling Office 365 subscriptions for a while and I never bought one. Eventually, I bought one from Amazon. So it is both true that I got it from Amazon, but that Microsoft had them prior.
There it was originally called "Hellbanning"
Patents are a joke.
Also they filed in 2012, it just took seven years to grant.