Some one help me please. What happens if a company has shares that are never purchased?

by Elisa
(Indiana)

Okay my question is regarding companies who have penny stocks. If a company is new to the market and they have say 10 million shares and only 7 million are purchased by the public what happens to the other 3 million?

I am wathcing a company and the stock fluctuates about 20 cents a day, thats a good day trade but my worry is will my shares sell if the company still has unpurchased shares? Is this possible?