Of course that is how the market cap is calculated, but the intrinsic value of the company (it's net assets, true value, potential, undervalued companies...) could be different, and that is why SP fluctuates changing MC of the company as the SP rises and falls...the company continues to trade meanwhile...and the SP rises as market sentiment changes..or as the company performs...
BLY Price at posting:
1.3¢ Sentiment: Buy Disclosure: Held