Justin brought up a great question yesterday. Because securing funding for one's own education would likely be the greatest use of entering the Human Stock Market. But, buying and selling shares in minors would be problematic, and super creepy knowing you don't really have their consent.
So, I think an 18-year old minimum age is probably a great idea. But also hurts what I think might be a big market - helping put promising third-world children through primary school as well as college in hopes of both helping them succeed and profiting on the success.
Justin hypothesized regulation to prevent monopoly ownership or employer influence. The monopoly question is a great one. What if we make it so that no individual can give up majority ownership in their stock. The individual must always possess at least a 51% share. That would also keep the individual as the primarily "decision-maker" over their own life plan. Can you imagine a meeting where your Board of Directors tells you to give up writing to become a mechanic?
As far as employer influence, why shouldn't an employer be able to buy someone's stock before hiring them? I don't exactly know why they'd want to, because it would just be like taking money out from one pocket and putting it in the other, especially if the job was this person's sole income. But if they think this person is going to go places, sure, the more power to them.
What else do we need to think about ?