In April, a huge negative SEO debate sparked up and it resulted in Rand Fishkin, the CEO of SEOmoz offering his site up as a sacrificial lamb to the negative SEOs out there to try to see if they can't hurt SEOMoz's rankings by implementing negative SEO techniques.
A week or so ago, SEOmoz received and unnatural link warning. SEOmoz explained it is likely because of the negative SEO challenge, where Google saw a ton of bad links coming in and issued the notification because of it.
But did it hurt SEOmoz? It doesn't appear so.
(1) The warning went out the same time everyone else got that new batch of link notifications - meaning, Google doesn't penalize for those specific links but rather just warns you that you have a nice number of links they are ignoring.
(2) SEOmoz shared their traffic from Google and there was no change at all:
Now the question is, did negative SEO beat SEOmoz's link graph? It depends on how you define beat?
(1) Yes, they did get tons of bad links to their site.
(2) Yes, they did get a link notification.
(3) No, their rankings did not suffer.
(4) No, this notification is not a penalty notification.