Short answer. Generally no. Inducing a worker who is already employed to quit in order to offer him to another is a prohibited practice, and even attempting it is covered. There is one exception: a transfer designed to free the worker from oppressive terms and conditions of employment.
What the law says
To induce or attempt to induce a worker already employed to quit his employment in order to offer him to another unless the transfer is designed to liberate the worker from oppressive terms and conditions of employment
Labor Code, Article 34 — Prohibited Recruitment Practices. Read the full provision →
What the clause actually forbids
The prohibited act is to induce or attempt to induce a worker already employed to quit his employment in order to offer him to another. Three elements are doing the work. The worker must already be employed, so this is not about approaching someone between jobs. The inducement must be to quit, not merely to consider a future move. And the purpose must be to offer him elsewhere — the recruiter's placement is the reason the resignation is being urged. Take any one of those away and the clause does not bite.
The exception is about the job you are in, not the one offered
The proviso permits the approach where the transfer is designed to liberate the worker from oppressive terms and conditions of employment. Read that carefully, because it is easy to invert. It does not say a recruiter may induce you to resign whenever the new job is better paid. The justification has to come from the conditions you are leaving — terms that are oppressive, not merely unglamorous or badly compensated. A recruiter who wants the benefit of this exception is asserting something about your present employer, and that assertion has to be true.
Why the law is suspicious of the approach at all
It is not the worker's ambition the section distrusts; it is the recruiter's incentive. Every placement is a fee, so a recruiter has a standing reason to talk employed people out of stable jobs, and the person carrying the risk of the move is never the recruiter. That is why attempt is included: the harm the law is guarding against begins with the persuasion, not with the resignation letter. It is also why the exception is written around the worker's liberation rather than around the agency's opportunity.
Before you resign anything
Get the offer in writing, in the name of the employer who is supposed to be hiring you, and do not treat a recruiter's assurance as the offer. Ask what the recruiter is being paid and by whom. Keep the messages in which you were urged to resign — if the placement evaporates after your resignation is accepted, those messages are the record of what was induced and why. If you have already resigned and the job never appeared, take that thread and your resignation letter to a lawyer promptly.