Because privately held companies do not sell shares on any public stock exchanges like the NYSE, they are not required to file a 10-k with the SEC. This means that there are no convenient, public forms to which to refer when you want to learn about a company's operations. Consequently, it can be very difficult to find any information about a privately held company.
There are exceptions, of course. If a private company is very large, like Mars, Inc., makers of candy and confectionery like 3 Musketeers and Mars bars, it will leave a "footprint" of sorts in the business news. And very large privately held companies like Mars, Inc. will often feature websites with information about the company, although this information isn't nearly as detailed as what you'd find in a 10-k. And smaller private companies, like your local non-chain bakery or other retailer, are almost impossible to investigate.
Image by 3Musketeers/Instagram
The best way to research private companies is by looking for articles about them in the business news press. Many larger private companies, particularly those that employ more than about 50 employees, will get significant attention from the press. The best places to find these articles is in one of our business databases. Please refer to the tab in this guide on library databases with business news articles to learn more about searching for news articles about private companies.