Short answer. No. Ratification is the act of the party who could have asked the court to annul the contract, and it takes effect without the conformity of the other side. The party who has no right to sue for annulment cannot block the ratification, and cannot insist on being asked first.
What the law says
Ratification does not require the conformity of the contracting party who has no right to bring the action for annulment.
Civil Code, Article 1395 — No Need for the Other Party's Consent. Read the full provision →
Ratification is a one-sided act
Article 1395 of the Civil Code states it in a single line: Ratification does not require the conformity of the contracting party who has no right to bring the action for annulment. A voidable contract is valid and binding until a court annuls it, and only one side holds the power to have it undone — the party whose consent was defective, or who was legally incapable when the agreement was made. Ratification is that party choosing to keep the contract instead. Because the choice belongs to him alone, the other party's agreement adds nothing; the contract is simply confirmed and the power to annul it disappears.
Who actually holds the right to annul
The rule only makes sense once you see who can sue. The action belongs to the person the defect protected: the one who was misled by fraud, forced by violence or intimidation, kept in error by a mistake, worn down by undue influence, or who lacked capacity to give consent at the time. The party who caused the defect, or who benefited from the other's incapacity, has no such action. That is precisely the person Article 1395 describes, and it would be an odd law that let the wrongdoer veto the injured party's decision to go ahead with the bargain anyway.
What ratification does — and what it cannot fix
Once made, ratification cleanses the contract of its defect from the beginning, so it is treated as having been unimpeachable all along, and the annulment action is gone for good. It may be express, by a clear declaration, or implied, by conduct — accepting the benefits, demanding performance or continuing to pay after the pressure has ceased and the true facts are known. What ratification cannot do is rescue a contract that was void from the outset, such as one with an unlawful cause or one the law forbids altogether. Nothing the parties say confirms an agreement the law refuses to recognise at all.
Why this matters in practice
The practical danger runs the other way from what most people expect. If you believe you were tricked or pressured into signing, silence and continued performance can be read as ratification, and you can lose the right to annul without ever meaning to give it up. Note too that the action to annul carries a time limit, counted from the moment the defect ends or is discovered, depending on the ground. So if you are considering attacking a contract, be careful about accepting further benefits under it, keep the records that show what you knew and when, and take advice before you act.