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how can i find if i can buy shares of a specific company?
user
a company whose stock is available for sale to the public is called a publicly-held or publicly-traded company.  a public company's stock is sold on a stock exchange, and anyone with money can buy shares through a stock broker. this contrasts with a privately-held company, in which the shares are not traded on a stock exchange. in order to invest in a private company, you would need to talk directly to the current owners of the company. finding out if a company is public or private is fairly easy.  one way to check this is to look at the wikipedia page for the company.  for example, if you take a look at the apple page, on the right sidebar you'll see "type: public", followed by the stock exchange ticker symbol "aapl".  compare this to the page for mars, inc.; on that page, you'll see "type: private", and no stock ticker symbol listed. another way to tell: if you can find a quote for a share price on a financial site (such as google finance or yahoo finance), you can buy the stock.  you won't find a stock price for mars, inc. anywhere, because the stock is not publicly traded.
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