Over-the-Counter Bulletin Board, or OTCBB, is a quotation service largely overseen by FINRA (formerly known as NASD). Unlike Pink Sheets, which is just a quotation publisher, OTCBB maintains listing requirements (though they're less stringent than those of an exchange). For this reason, OTCBB has a little bit of added legitimacy.

Pink Sheets is a system that provides investors with quotation information on stocks that are registered with it. Unlike OTCBB, however, Pink Sheets isn't registered with the SEC and doesn't enforce any listing requirements. Bottom Line: Pink Sheets stocks are risky.

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