Answer by hroptatyr for Does a stock's price represent current liquidation of all shares?

Is the stock's price at any given moment the price at which all shares could be sold to new investors?

No. For the simple fact that the current bid/offer always have sizes associated.

What you should be looking at is the consolidated price to buy/sell X shares (10bn doesn't really work as not everyone is willing to sell/buy).

If you look at the spread of the consolidated price at your quantity level, you'd notice it would be in stark contrast to the spread of the best bid/offer but (by definition) that would be the price to buy or sell X shares to new investors.

Edit
Calculation of the consolidated price of X shares: You go through the order book and calculate the size-weighted average price until you covered X.

Example:

    bids 1000 40.00 1000 39.80 1000 39.60

So the consolidated price for 3000 shares would be $39.80, the consolidated price for 2000 shares would be $39.90.