The most important thing to know before you begin your research is whether your company is publicly held or privately held. This information will inform where you search for information. U.S. law requires pubicly held companies to disclose certain information. Most private companies opt not to disclose this information. Thus, if you are researching a small private company, you may need to rely on local news and information sources. 

PrivCo is the best source to research privately-held companies. PrivCo has in-depth information for privately-held companies. Need business info on Red Bull or NASCAR or Gucci or the European PGA Tour? This is information (particularly financials) that is NOT available elsewhere.

Mergent Horizon is the best source for information on industries and publicly-traded companies. It includes a comprehensive database of US-traded companies organized by the goods and services from which they drive their revenues as well as their key business relationships. Horizon's Hierarchy function maps companies from the bottom up (based on actual products and services), then filters through 16,000 product levels into a searchable structure -- resulting in data and insights on performance, trends, and interrelationships.

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