B3 was created in 2017 when BM&F Bovespa merged with CETIP.
The name B3 refers to Brasil, Bolsa, Balcão, meaning Brazil, Stock Exchange, Over-the-Counter. The merger combined BM&F Bovespa's securities and derivatives activities with CETIP's important role in custody, registration, and over-the-counter financial markets.
B3 is headquartered in São Paulo and is Brazil's principal exchange and financial market infrastructure institution. It supports trading and settlement in equities, derivatives, fixed income, exchange-traded funds, and other products.
A common mix-up is treating B3 and Bovespa as interchangeable names. Bovespa was the Brazilian stock exchange associated with São Paulo and later formed part of BM&F Bovespa; B3 is the post-2017 organization. The company's name is short, but it represents a broad marketplace rather than only ordinary shares.