Pinksheets can provide some background also recommend message boards that may provide additional information where pinksheets may lack. Utilize Bing and Google to type in the ticker and company name or your favorite search engine. TD Ameritrade and Scottrade sometimes will provide bits and pieces.
SOS filings, third parties that companies claim to be doing business with, management backgrounds etc...
Be careful when you see a CEO of one company and he is the CEO of 3 or 4 more. Also, be VERY careful of CEO's who have no experience in the business they are running! i.e. an oil and gas company CEO who only has experience in venture capital or mortgages etc...
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