Over-the-counter (OTC)
Plain definition. Over-the-counter (OTC) trading generally refers to any trading that takes place off an exchange, and many financial products trade this way, including stocks, bonds and currencies.
Technical definition. FINRA describes OTC trading as trading that generally refers to “any trading that takes place off an exchange,” covering stocks, bonds, currencies and various derivatives. In equities, exchange-listed stocks may trade on an exchange or OTC, while unlisted equities trade only OTC. These trades run through off-exchange execution venues such as alternative trading systems (ATSs) and broker-dealers acting as wholesalers.
On this site
On this site, Over-the-counter (OTC) comes up in How deep is XRP’s market liquidity, and is it enough for global settlement? and How do XRP ETF creations and redemptions work, and who moves the XRP?.
Source
A Look at Over-the-Counter Equities Trading | FINRA.org (finra.org), read October 1, 2026.