"It also only applies if one is fired from said previous employer, not one who's left at will."
?
Are you referring to California here, or non-competes in general? If the latter, I'm, pretty sure that you're incorrect. " The use of such clauses is premised on the possibility that upon their termination or resignation, an employee might begin working for a competitor or starting a business,..." (top of same Wiki page)
Huh? Every non-compete I've had forced down my throat (I've refused to sign the last several) was specifically guarding against me leaving the company for a competitor.
Except as provided in this chapter, every contract by which
anyone is restrained from engaging in a lawful profession, trade, or
business of any kind is to that extent void.
Its CA law. From the business and professions code [1].
A clause restraining you from engaging in your "profession, trade, or business", i.e. in general, is unenforceable. A clause restraining you from engaging with another party may or may not be unenforceable depending on the details.
In other words, nobody can enforce a clause preventing a programmer from programming for company B after leaving company A purely on the basis of restricting competition.
They may have a case if e.g. company B contracted company A to do some work and then bought out company A's programmer (e.g. to save money), but only if the contract between company A and the programmer in question has a restraint specifically penalizing this scenario.
(Even then, it doesn't mean companies will choose to enforce the contract. I've worked for companies where the restraint was between the companies A and B, and in the interest of preserving business relationships, company A decided not to pursue their legal right to recourse when company B poached an employee from A; the employee did not break conditions of their employment with A as the restraint was between their companies.)
"It also only applies if one is fired from said previous employer, not one who's left at will."
?
Are you referring to California here, or non-competes in general? If the latter, I'm, pretty sure that you're incorrect. " The use of such clauses is premised on the possibility that upon their termination or resignation, an employee might begin working for a competitor or starting a business,..." (top of same Wiki page)