Brazil's Ambipar jumps after controlling shareholder has stake reduced

** Shares in Brazilian waste management firm Ambipar AMBP3 jump after its controlling shareholder claimed to have had his stake reduced due to an "irregular transfer" of shares

** Shareholder Tercio Borlenghi Junior tells Ambipar that he had his stake diminished from 73.5% to 67.7%

** He attributes the reduction to an "illegal transfer of shares, with no authorization" by lender Bradesco BBDC3 and Genial Investimentos, together with a vehicle linked to Grupo Opportunity

** The transfer follows a preliminary injunction secured by Ambipar at a local state court to temporarily prevent the accelerated maturity of its debt

** Borlenghi Junior argues the transfer occurred against the judicial decision, which allows the protection of Ambipar's assets while it seeks a viable alternative with creditors

** Ambipar's shares are up more than 9% in midday trading, paring some gains after jumping as much as 54% earlier

** Year-to-date, Ambipar is down more than 93%