10-20K the average - I agree, 'leafs. I'm very sure some have 100,000+ shares here, not many with half million, though.
I would consider a big shareholder to have 50,000 or more. Another definition would be someone who is an investor and has over 30% of their investment capital in NOT - that would be quite big for that individual. As to those who have that percentage or greater, be careful. I remember a couple of years ago, some phony posting how he'd mortgaged his house to buy more NOT and everything he had was in it, plus much borrowed capital. He was supposedly buying while the stock was on its run from .25 or so, right up to $7. Told him that was very unwise, and he scoffed as did others around here.