Ownership of work product does not follow the paycheque automatically. In most countries an employee's inventions and creative work pass to the employer only if the contract says so, and contractors keep everything unless they sign it over. An IP assignment fixes that in writing, usually alongside a confidentiality agreement.
What the clause needs
A present transfer ("hereby assigns"), not a promise to assign later. It should cover inventions, code, designs and content created in the course of the work, include a moral rights waiver where local law allows it, and add a duty to help with patent filings after the person leaves.
Where local law limits it
Germany requires employers to claim employee inventions formally and pay for them. France does not allow authors to waive moral rights. California stops employers claiming inventions made on the employee's own time. A clause copied from one employment contract to another country may be partly unenforceable.
Why it matters when hiring through an EOR
The Employer of Record is the legal employer, so IP flows to them first. It only reaches you if their employment contract captures it and the service agreement assigns it onward. Check both before onboarding anyone whose output you plan to patent or sell.