We know that many firms are listed on different stock exchanges. According to ArcelorMittal's website:

ArcelorMittal is listed on the stock exchanges of New York (MT), Amsterdam (MT), Paris (MT), Luxembourg (MT) and on the Spanish stock exchanges of Barcelona, Bilbao, Madrid and Valencia (MTS).

When I look the company up in a financial website, such as MarketWatch, it reports a market cap of $12.23B for the company as of today. What does this market cap number represent? Is it the value of all the stocks listed on all of the exchanges, or is it just the value of shares listed on the New York Stock Exchange? Apologies for my amateurishness!

  • 2
    Does this answer your question? Company stock listed in multiple exchanges?
    – D Stanley
    Commented Sep 28, 2020 at 2:11
  • I was asking a much simpler question indeed. Theoretically, each exchange might report the market cap of the stock in that specific exchange . For example, if a stock has 400 shares outstanding in NYSE and 300 shares in Tokyo, and the price is 10$ everywhere, the market might report 4000$ market cap in nyse and 3000$ in Tokyo. As I digged more, it appears to me that this does not happen, and the financial data websites report the total market cap i.e. the total number of shares across all exchanges times the price (but which price? since there might be slight differences). Still not sure. Commented Sep 29, 2020 at 8:16
  • 1
    I still think you misunderstand a bit. The shares are the same shares across all exchanges. The exchange does not "have" the shares - they just facilitate the trades among the public owners. The number of shares is the number of outstanding shares reported by the company (not the exchange). The price should be pretty close across all exchanges also (otherwise there would be an arbitrage possibility) so it shouldn't make a large difference.
    – D Stanley
    Commented Sep 29, 2020 at 12:41
  • 1
    Yes, I did misunderstand! Thanks a lot for clearing that up for me. So a hypothetical firm might go public by an IPO and get listed on NYSE, and then some years later get listed on Barcelona exchange. In such case, there is no need to issue or sell new shares in the Barcelona exchange. It would be the same shares now being traded both in NY and Barcelona. Did I get it correctly this time? Commented Sep 29, 2020 at 13:01
  • 1
    Yes that is correct. The exchange is just a facilitator.
    – D Stanley
    Commented Sep 29, 2020 at 13:05

1 Answer 1


The market capitalization (market cap) of a company is calculated as the total shares outstanding multiplied by the price.

It doesn't matter where the stock is listed: it could be one exchange, multiple exchanges (as in your example) or no exchange at all for small/micro cap stocks that only trade OTC.

You should be able to find the total number of shares outstanding in the financial disclosure documents of the company.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .