If someone makes a bid for the company that is accepted by the majority of the shareholders, management has absolutely no right to over ride that decision. Anyone voting yes for this is cerifiably insane IMO.
TGiff- If the issue is inadequate voting power for B shares increase the voting rights of those shares (10 votes v 5 votes). I'm willing to go for this (with trepidation). I will not (currently) vote for dillution of my shares.