Read up on Sabu and the timeline of events between his initial arrest and the various Anonymous Operations. He's a narc, has admitted it and was very much involved in most of the operations. Coincidentally, most people in those operations were rolled on and his assistance has been used in their arrests/cases.

So this was referring to the Lulzsec attacks carried in the few months between Sabu's arrest and their demise.

I wouldn't call that "much of Annonymous".

http://edramalpl7oq5npk.onion/Sabu is a good explanation