The OTC (Over-The-Counter) Bulletin Board or OTCBB was a United States quotation medium operated by the Financial Industry Regulatory Authority (FINRA) for its subscribing members.
[2] FINRA, an "independent, not-for-profit organization authorized by Congress", ran and provided regulatory services to the OTCBB by "writing and enforcing rules governing the activities of more than 4,100 securities firms with approximately 639,780 brokers".
[3] The OTCBB formerly collected 100% of quotes, but that number declined with the rise of its competitor OTC Markets Group, which uses an electronic quotation system.
Both retail and institutional investors generally avoid them, because of fears that share prices are easily manipulated and the potential for fraud.
For a time, FINRA believed that the proposed "quotation consolidation system" would enhance transparency, thereby decreasing the potential for price manipulation or fraud.