[btilly]

The relevant difference as I understand it is the definition of "the scope of the employment".

In both states, if a professional employee figured out how to solve a work problem at 6 AM in the shower, that is clearly part of the scope of the employment. The difference is that if a programmer sits down to write some code at 8 PM, that is more likely to fall within the scope of employment in New York than in California.

This difference is on top of what the contract is allowed to say.