merger of the São Paulo Stock Exchange (Bovespa) and the Brazilian Mercantile and Futures Exchange (BM&F), creating the world's second largest stock exchange. As a result of an early 2008 stock swap, Chicago's CME Group owns a 5% stake in BM&FBovespa, and in turn, BM&FBovespa owns a 5% stake in CME Group. The agreement has also created an order routing trading system between both exchanges. On June 18, 2012, BM&FBovespa became a founding member of the United Nations Sustainable Stock Exchanges initiative on the eve of the United Nations Conference on Sustainable Development (Rio+20). On June 16, 2017, the Securities and Exchange Commission of Brazil has approved the change to the corporate name of BM&FBOVESPA S.A. – Bolsa de Valores, Mercadorias e Futuros to B3 S.A. – Brasil, Bolsa, Balcão, which must be used in all formal communications and references to the Company. The merger of Cetip S.A. – Mercados Organizados into B3 S.A. – Brasil, Bolsa, Balcão was approved both at the Extraordinary Shareholders Meeting held on June 14, 2017 and by CVM, and that the action shall occur on July 3, 2017. Hours The exchange has a pre-market session from 09:45am to 10:00am, a normal trading session from 10:00am to 5:30pm and a post-market session from 6:00pm to 7:30pm weekdays and holidays declared by the Exchange in advance. Tickers and trade names In the cash market, tickers are composed by four letters, a number, and a suffix in some cases. The letters stand for the listed company and the number disclosed the equity type, as follows: 11 and onward, codes may represent many situations, most commonly units (UNT, a certificate meshing different equities together. For instance, SULA11 is a unit comprising one common stock and two preferred stocks issued by Sul América S.A.), exchange-traded funds, real estate investment funds (known as FII, REIT in English) and Brazilian Depositary Receipts (BDRs). Nevertheless, they may state other conditions, as debenture subscription rights, special situations, and so on. It is important to note that "classified" preferred stocks (A, B, C, D and furthermore) do not have an implicit meaning, i.e., each issuer may attribute different rights and restrictions for a given class. This means it is mandatory to learn individually their characteristics as they are not directly comparable among companies. The suffix B after the ticker means the equity is traded at the over-the-counter (OTC) market. Here are some examples: VALE5