Basically allows anyone in the US to trade through almost any broker as opposed to a limited number of brokerage firms, without paying fees other than the usual fee charged by the brokerage firm. Also allows mutual funds that were restricted from purchasing to purchase shares easier.
The OTCQX® Best Market is for established, investor-focused U.S. and international companies. To qualify for the OTCQX market, companies must meet high financial standards, follow best practice corporate governance, demonstrate compliance with U.S. securities laws, be current in their disclosure, and have a professional third-party sponsor introduction. Penny stocks, shells and companies in bankruptcy cannot qualify for OTCQX. The companies found on OTCQX are distinguished by the integrity of their operations and diligence with which they convey their qualifications.
This is my take on it. Others might be able to explain more.
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