Growing up as free office labor, pulling cases, typing my father's briefs (get your mind out of the gutter please), I can say, without a doubt, not only is my IQ negative, it's sub par as well.
Maybe, since I don't know what a negative IQ is. Accepting that that old outmoded measure proposes that an IQ of 100 is normal, ie, represents the problem solving capacity of the majority of the population, that below an IQ of 80 a person is incapable of caring for themselves, that above 120 is very bright and above 140 is genius... where in this system is a negative score or minus-something? of under zero? One might guess that such a score was only "possible" for a being with no nervous system with which to compute. The irony of that tickles a good silent laugh.