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Public vs Private Companies
Center for Business Research


What is a public company?
A public company sells stock to the general public and the stock is traded on an exchange.


What is a private company?
A private company does not sell stock to the general public, and the stock is not traded on an exchange. In private firms, the stockholders are usually the principals in the company (e.g. founders, members of their families, key employees, etc.).


Why is it important to know whether a company is public or private?
When you know what type of company you have, the research process is much easier. There is a great deal of information available on public companies. Public companies are required to file specific reports with the U.S. Securities and Exchange Commission (SEC). The 10-K is the official annual report filed with the SEC each year. Companies must file their 10-K reports within 90 calendar days of the end of their fiscal year. For companies with a fiscal year-end of December 31st, reports must be available no later than April 1st.

Private Companies do not file with the SEC and have no obligation to make their financial information public. Therefore, sometimes there is almost no information available for a private company beyond its own web page or a brief directory listing. Such a listing may provide only contact information, number of employees, and lines of business. If a private company has been in the news, there is also the possibility of finding newspaper and magazine articles.


How do I tell if my company is public or private?
There are a number of sources that will let you know if your company is public or private. Try these:

  • Million Dollar Directory (Bus HC 102 .D8)
    A triangle symbol next to the company name indicates whether the company is public.

  • Directory of Corporate Affiliations (Bus HG 4057 .A217)
    Check the master index to this multi-volume set. The index listing will tell you whether your company is a public company, private company or an international company.

  • Business & Company Resource Center and General BusinessFile ASAP
    These databases provide company profiles and many full-text articles on public and private companies. The profile will indicate the status of the company.


Good Sources for Public Company Information:


Good Sources for Public and Private Company Information:



Lori Cimino, Linda McCormack &
Andrea Scoma; cbr@cwpost.liu.edu

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