The head of the Abradin group, Aurelio Valporto, said it asked for an investigation of the deal. Abradin also filed a complaint with the European Commission two months ago arguing that the acquisition of Embraer SA's commercial division by Boeing Co creates hurdles to competition in the Brazilian aerospace industry.
Former leftist presidential candidate Ciro Gomes also filed a complaint with the Brazilian antitrust watchdog and is seeking an injunction from Brazil's Supreme Court to block the deal.
Embraer said in a statement that it is working with global regulators on the Boeing deal, which has been approved in the United States, China and Japan. The company said it will continue to cooperate with other regulators.
(Reporting by Alberto Alerigi Jr; Writing by Tatiana Bautzer; Editing by Dan Grebler)