If you have a dispute and are thinking about suing, there is something you should know before taking the step: since 2025 the law requires you to try to resolve it through agreement before going to court. That attempt has a technical name, the MASC, and it is not a mere formality: if you skip it, your claim can end up shelved without a judge ever examining the merits.
In this article we explain what MASC are, what exactly the law requires of you, in which matters they apply, and what the consequences of ignoring them are.
What MASC are
MASC stands for Appropriate Dispute Resolution Methods (Medios Adecuados de Solución de Controversias). It is the label that groups together a series of routes for resolving a dispute without needing to go to trial, or at least without going straight to it.
The underlying idea is simple: many lawsuits can be avoided if the parties sit down to talk in a serious and structured way. MASC aim precisely at that, easing the courts’ workload and offering you a faster and cheaper way out than court proceedings that can last years.
What Law 1/2025 requires
The Law 1/2025 on the efficiency of the public justice service turned attempting a MASC into a procedural requirement. In force since 3 April 2025, this means that, before filing a claim in civil or commercial matters, you must prove that you have attempted in good faith to resolve the matter through one of these methods.
In practical terms: when you file the claim, you must attach proof that there was a prior attempt to reach an agreement. Without that proof, a requirement for the proceedings to move forward is missing.
This does not mean you have to reach an agreement come what may. The law does not require you to compromise or waive your rights. What it requires is that you have attempted it seriously.
In which jurisdictions it applies
The requirement applies in civil and commercial matters. This covers most disputes between individuals and between businesses:
- Claims for a sum of money and unpaid debts.
- Breaches of contract.
- Disputes between partners in a company.
- Matters relating to property owners’ associations.
- Many issues concerning inheritances and civil liability.
It does not apply to criminal or administrative litigation, and some civil matters are excluded (for example, those affecting fundamental rights or certain sensitive family matters). If you are unsure whether your case is in or out, that is exactly the kind of question worth consulting with a lawyer before making a move.
“At BBM Abogados we defend the interests of individuals and businesses in Santander and Cantabria with a close, rigorous and fully transparent approach. If you have doubts about your case, we help you see it clearly.”
What types of MASC exist
The law does not require you to use a specific one: it lets you choose the one that best fits your dispute. The main ones are:
- Direct negotiation between the parties, usually through their lawyers.
- Mediation, with a neutral third party who helps bring positions closer without imposing a solution.
- Conciliation, before a third party who can propose solutions.
- Confidential binding offer, in which one party formally proposes a solution to which it is bound if the other accepts it.
- Independent expert opinion on the point in dispute.
The important thing is that there is documentary evidence of the attempt: who proposed it, when, what was offered, and how the other party responded.
What happens if you sue without attempting it
The direct consequence is the rejection of the claim. The court does not assess who is right: it finds that a procedural requirement is missing and does not allow the proceedings to move forward.
This translates into lost time. You will have to backtrack, attempt the MASC first, and file the claim again afterwards. In a dispute where time is against you, that delay can be a serious problem.
How it affects the costs
Here is one of the points most worth understanding. The reform allows the judge, when deciding who pays the costs of the case, to assess how each party behaved during the attempt to reach an agreement.
If you unreasonably reject a reasonable offer and then obtain a similar or worse outcome at trial, that attitude can turn against you in the decision on costs. And the reverse is true: having made a sensible and documented proposal strengthens your position. That is why it is not enough to “tick the box”: the way you do it has real effects.
The role of the lawyer
You might think that, since it is about negotiating, you do not need help. In practice it is the opposite. A good MASC attempt requires strategy: knowing what to offer, how much, at what moment, and how to document it so that it serves as evidence and protects you in a future trial.
The lawyer prepares the request, assesses whether the other party’s offer suits you, formally records the attempt, and preserves your position with a view to the costs and the subsequent proceedings. A poorly planned MASC can weaken you even when you are in the right.
At BBM Abogados, a firm in Santander since 1990, we handle the prior attempt to reach an agreement and, if it does not succeed, we take the next step. When the dispute is an unpaid debt, we link it to the debt claim route or, where appropriate, to an order for payment procedure. Call us on 942 36 10 48 or write to us from /contacto/ and we will study your case.