BV can mount a takeover bid at whatever price he likes. But he...

BV can mount a takeover bid at whatever price he likes. But he needs to convince enough shareholders to accumulate 90% of total shares on issue. Once he does that the remaining 10% can be compulsory acquired. I understand he's nearly at 60%. Not a huge percentage to go to take control. Only thing I'm not sure of is that if he is intending mounting a takeover bid, shouldn't he have to announce his intentions to do so whenever his holding percentage changes?