The market price is defined as the price at which people buy. Currently, shares are sold and bought at slightly above IPO prices, so that is the current market price.

Instead of making one big offering of new shares at some more or less arbitrary below market price, it would also be possible to introduce new shares in a piecemeal fashion over an extended period of time and sell them at market price. The price of the shares would adjust downwards in both cases, but in the second scenario no shares would be sold at artificially low prices and the price would adjust gradually instead of spontaneously.