alt Hacker NewsSilver lining: given the leaked financials of OpenAI, he might very well be joining a sinking ship.
Also, why didn't they nail him down contractually when they bought character.ai ... isn't that pretty standard with these type of superstar (re)hires?
You can't force someone to keep taking your money (that's indentured servitude), you can only incentivize them to stay with increasing amounts of money. Google almost certainly did do that. Probably by vesting his hiring bonus over 2-3 years.
OpenAI is in a unique position right now to grant pre-IPO options (probably in the form of RSUs). And they wanted him badly enough to grant the extra options necessary to effectively 'buy out' whatever unvested Google bonus he's walking away from.