> independent contractors are free to sub out work. this is the law.

Practically speaking, there is no way a software contractor can sub out work without violating a litany of contractual obligations in the contracting agreement. Even minimalistic contracting boilerplate agreements will have clauses that cover these situations.

For example, if you sign an NDA with a company covering the work and then turn around and send the codebase to a contractor in Romania to work on it, you've very clearly violated the terms of the NDA.

So no, the law doesn't automatically allow engineering contractors to do whatever they want with the work.