I recently read an article in WallStreetMojo with discusses the top differences between a private and public company. As mentioned several times above, a public company is able to sell their shares to the public (millions and millions of shareholders). A private company can sell their shares to only a few investors who are willing to buy. The second difference is that in a public company, the stocks are traded on stock exchanges. A private company’s stocks are traded by private investors. A public company has to follow regulations issued by SEC while private companies do not. For private companies, this hold true until they have reached $10 million and more than 500 shareholders. Another difference is how the companies secure their funds. A public’s company source of fund is by selling its shares and bonds. A private company receives funds from private investors.

Examples of public companies are Citigroup, Bank of America, JPMorgan Chase.
Examples of private companies are Koch Industries, Bechtel Group, Mars.