You're misunderstanding things. There's no law that companies have to know where their employees are working from. It's simply a consequence of the fact that governments have sovereign power to regulate things within their borders, including employment. Companies that pay to have work performed within state X generally [1] have to follow those regulations. If an employee moves to another jurisdiction and the employment agreement is not compatible with applicable local laws, then there are two main options: The relationship can be terminated or it can be brought into compliance.
If a company has employees in all 50 states, then yeah they need to have compatible employment practices with all of them (plus the respective cities those employees work from, for extra fun). In practice this doesn't come up much because most employment regulations are minor and most governments have similar rules.
[1] there are a million qualifications to this, speak to a lawyer if you want details about your particular case
If a company has employees in all 50 states, then yeah they need to have compatible employment practices with all of them (plus the respective cities those employees work from, for extra fun). In practice this doesn't come up much because most employment regulations are minor and most governments have similar rules.
[1] there are a million qualifications to this, speak to a lawyer if you want details about your particular case