Diagnostic

Amparo for companies after the 2025 reform: narrower and more demanding

No general effects, a stricter standard for legitimate interest, and new cases in which a stay is denied. It still works, though differently.

LEXURE Administrative and Constitutional Litigation Practice Team 7 min read Regulatory status verified in 2026

For years, many com­pa­nies saw amparo (con­sti­tu­tional injunc­tion) as a tool to imme­di­ately halt a law or an act of author­ity while the merits were argued. The amend­ments to the Amparo Law (Ley de Amparo) pub­lished in 2025 changed that cal­cu­la­tion. Amparo remains the main con­sti­tu­tional defense, although it now requires more prepa­ra­tion and pro­tects only the party that files it; in addi­tion, a stay is granted only after a stricter anal­y­sis.

What the law requires

Dead­lines. The amparo claim must be filed within fif­teen days, with some excep­tions; against a self-exe­cut­ing gen­eral norm, the dead­line is thirty days (Arti­cle 17 of the Amparo Law). The period runs from the day after notice of the act takes effect or from when the party learned of it; for self-exe­cut­ing norms, from their entry into force (Arti­cle 18).

What it can be filed against. Indi­rect amparo is avail­able against gen­eral norms that cause harm by their mere entry into force or upon the first act apply­ing them, and it is the usual route against acts of admin­is­tra­tive author­i­ties (Arti­cle 107). It is not avail­able, among other cases, against acts expressly or tac­itly con­sented to and, in gen­eral, when the appli­ca­ble ordi­nary reme­dies have not been exhausted, sub­ject to the excep­tions the law itself pro­vides (Arti­cle 61).

Rel­a­tive effects. In pro­ceed­ings that rule on the uncon­sti­tu­tion­al­ity of gen­eral norms, judg­ments do not set gen­eral effects in any case (Arti­cle 73, amended on March 13, 2025), and a stay against gen­eral norms cannot be granted with gen­eral effects either (Arti­cle 148). If a law affects every com­pany in a sector, each one that wants pro­tec­tion must file its own pro­ceed­ing.

Legit­i­mate inter­est. Since the amend­ment of Octo­ber 16, 2025, the stan­dard is more demand­ing: a party claim­ing legit­i­mate inter­est must prove an indi­vid­ual or col­lec­tive injury that is real and dis­tinct from that of every­one else, so that annulling the act pro­duces a cer­tain, not merely hypo­thet­i­cal, ben­e­fit (Arti­cle 5, sec­tion I).

The stay. The court must expressly carry out a weighted anal­y­sis of prima facie merit (apari­en­cia del buen dere­cho) and the social inter­est, and verify that the act exists, that the peti­tioner has an inter­est in the stay, that the stay does not cause sig­nif­i­cant harm to the com­mu­nity, and that there is prima facie merit (Arti­cle 128). The same amend­ment added cases in which a stay is deemed to harm the social inter­est, includ­ing allow­ing activ­i­ties that require a fed­eral permit, autho­riza­tion, or con­ces­sion to con­tinue when the party does not hold one, or obstruct­ing access to finan­cial infor­ma­tion for the pre­ven­tion of trans­ac­tions involv­ing pro­ceeds of illicit origin (Arti­cle 129, sec­tions XIV to XVI).

Bond and counter-bond. If the stay may cause harm to a third party, the peti­tioner must post suf­fi­cient secu­rity to com­pen­sate for it if it does not obtain a favor­able judg­ment (Arti­cle 132). Even once granted, the stay can fall away: it ceases to have effect if the inter­ested third party posts a counter-bond to restore things to their prior state and pay dam­ages if the amparo is granted, unless enforce­ment would render the pro­ceed­ing moot or make it very dif­fi­cult to restore things (Arti­cle 133).

What you obtain if you win. When the act is pos­i­tive, grant­ing the amparo restores the peti­tioner to the enjoy­ment of the vio­lated right and returns things to their prior state; when the act is neg­a­tive or an omis­sion, it requires the author­ity to respect the right and comply with what that right demands (Arti­cle 77).

The tran­si­tion. Under the Third Tran­si­tory Arti­cle of the decree of Octo­ber 16, 2025, com­pleted stages are gov­erned by the prior rules and later pro­ceed­ings by the new ones. How this applies to pend­ing cases is a matter of judi­cial cri­te­ria that are still taking shape.

What to do and by when

  1. When a new norm affects your com­pany, assess within the first few days whether it is self-exe­cut­ing, because the thirty-day period runs from its entry into force.
  2. If the norm requires an act of appli­ca­tion, start pre­par­ing the file now to chal­lenge the first one you receive, within fif­teen days.
  3. Doc­u­ment the spe­cific and dis­tinct impact on your com­pany, with fig­ures and evi­dence, because it will be the basis for the inter­est and for the stay.
  4. Check whether there is an ordi­nary remedy that must be exhausted first, or whether your case falls within an excep­tion.
  5. If you need a stay, pre­pare the social inter­est anal­y­sis and the secu­rity before filing the claim.
  6. If your activ­ity requires a fed­eral permit or autho­riza­tion, reg­u­lar­ize it: with­out it, a stay is unlikely to be granted.

Recommendations to mitigate risk

The main risk is losing the means of defense. A claim filed late is inad­mis­si­ble, and an act not chal­lenged in time is deemed con­sented to. Nor will pro­tec­tion reach a com­pany that expected to ben­e­fit from another com­pany’s amparo, because judg­ments have no gen­eral effects. With­out a stay, more­over, the act is enforced while the merits are decided: the fine is col­lected and the clo­sure is car­ried out even if the case is ulti­mately won, and the chal­lenged norm must be com­plied with in the mean­time.

In a hypo­thet­i­cal sce­nario, a gen­eral norm enters into force and binds an entire sector from that day. One com­pany decides to wait and see what the others do. When another com­pany obtains a favor­able judg­ment, the thirty-day period has already expired and its com­peti­tor’s pro­tec­tion does not extend to it.

Self-assessment

Answer yes or no about your own com­pany.

  1. Do you have a pro­ce­dure to assess, within days, whether a new norm affects your com­pany by its mere entry into force?
  2. Can you tell the fif­teen-day period apart from the thirty-day period?
  3. Do you doc­u­ment the spe­cific eco­nomic impact that the norms and acts you chal­lenge have on your com­pany?
  4. Do you check whether there is an ordi­nary remedy you must exhaust before filing for amparo?
  5. Have you planned how to post secu­rity for a stay if you need one?
  6. Are your fed­eral per­mits and autho­riza­tions cur­rent?

How we approach it at LEXURE

We work with your man­age­ment team to assess the impact of each rel­e­vant norm or act, deter­mine whether amparo is avail­able, by when, and how likely a stay is, and we pre­pare the claim with the evi­dence the new stan­dard requires. We explain the risks and costs of each route clearly, with­out promis­ing results.

If a recent law or act of author­ity affects your com­pany, sched­ule a diag­nos­tic meet­ing with us while the dead­line is still open.

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Legal basis

  1. Amparo Law (Ley de Amparo), last amended DOF October 16, 2025, Articles 5, section I, 17, 18, 61, 73, 77, 107, 128, 129, 132, 133, and 148, and Third Transitory Article of the decree of October 16, 2025. Current text (opens in a new tab)
  2. Decree amending the Amparo Law, DOF October 16, 2025. Official text (opens in a new tab)

This note is for information only and describes the law in force on the verification date. It is not legal advice on a specific matter. It is a translation of the Spanish original: Mexican law is published in Spanish, and the official Spanish texts prevail.

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