CNPJ (short for Cadastro Nacional da Pessoa Jurídica in Portuguese, or National Registry of Legal Entities), is an identification number issued to Brazilian companies by the Secretariat of the Federal Revenue of Brazil (in Portuguese, Secretaria da Receita Federal).
Up to 1998, the CNPJ was known by the acronym CGC, which stands for Cadastro Geral de Contribuintes (General Taxpayers Registry).
The CNPJ consists of a 14-digit number formatted as 00.000.000/0001-00 — The first eight digits identify the company; the four digits after the slash identify the branch or subsidiary ("0001" defaults to the headquarters) and the last two are check digits.
References
CNPJ Wikipedia(Text) CC BY-SA