I'm thinking with ever increasing seriousness: let's split any company that grows past a certain size. Each side gets a copy of the codebase and half the assets, no one who's been on the board on one side can be on the other side's board, and neither side can buy off the other. They can use the existing branding for a limited time and with a qualifier (say Google Turnip vs Google Potato) but after that it's on the strength of the new brand which they're each building and for which they're competing against each other and the rest of the market.

This is not happening in my lifetime, of course it isn't. But by god does it need to happen.

Right? We need a "You won capitalism!" award where everybody in the org gets a huge bonus and then the company is split into small pieces and then they start over. On top of it we do what you describe and enforce the split so they can't collude.