The battle for Peru's only brewer Backus is being investigated from both sides by the stock market authority in the country CONASEV. And the market body has given all three parties involved five days to defend themselves against evidence of wrong-doings. CONASEV, said it had found signs of alleged collusion between Colombian brewer Bavaria and Venezuela's Cisneros Group over their purchases of major stakes in Backus within the space of a few days in July.