I'm guessing it was tied to shipping that autonomous car with no steering wheel that they made awhile back.
however - and this is page's big point - that payout has little to do with his overall contributions to the project, and rather that he had early responsibilties and stuck around.
http://fortune.com/2016/07/21/more-on-what-gm-paid-to-buy-cr...
It's the same bogus excuse for outrageous CEO pay: "We just can't seem to find anyone good without offering 1000X more than normal people make."
A $100MM bonus seems like a career-ending bonus to me. How do you keep going to work after that?
Sure, and the numbers get far larger than $100 million.
Larry Page and Sergey Brin for example, turned down very large acquisition offers, including for at least a billion dollars from Yahoo, at a time when they didn't even have a serious business model.
Mark Zuckerberg turned down several large offers for Facebook when it didn't have a serious functional business. He could have walked away nearly a billionaire before Facebook had even printed a dollar of profit.
Bill Gates turned away numerous, large acquisition offers in the first ~10 years of Microsoft's existence. IBM was interested in buying them for years.
The Snapchat owners turned down ~$3 billion from Google to go public instead as an exit. Even after the beating their stock has taken in the last few months, the market cap of Snap is $15 billion today.
from Facebook
Plenty of CEOs have career ending incomes / bonuses already.
Turning down $100mm when you have nothing of value yet is very different imo
Paying $100,000,000 up-front to someone who hasn't yet delivered the same success seems to be putting the cart before the horse.