From what I understood, it's not a matter of levels of abstraction: the system here really is simpler. According to BM&FBOVESPA's own website (http://www.bmfbo

From what I understood, it's not a matter of levels of abstraction: the system here really is simpler. According to BM&FBOVESPA's own website (http://www.bmfbovespa.com.br/pt-br/servicos/servicos-de-pos-negociacao/central-depositaria/central-depositaria.aspx?idioma=pt-br http://www.bmfbovespa.com.br/pt-br/servicos/servicos-de-pos-... - unfortunately in Portuguese only), it has fiduciary ownership of the assets, and individual accounts for each end investor. The brokerage doesn't "owns is an entitlement to stock" or similar; there's a single indirection layer. Your brokerage manages that account for you, but the account is in your name, not in the brokerage's name; you can even login directly to the bmfbovespa site (your login is your national tax ID) and monitor it.