The Administrative Law Chamber of the Supreme Court has established a criterion with direct scope on the way in which the Tax Inspection can justify its liquidation acts.
The judgment of July 7, 2026 (STS 3035/2026, ECLI:ES:TS:2026:3035, rapporteur Mr. Navarro Sanchis) declares contrary to law the practice of basing the same tax settlement on two mutually exclusive legal grounds, articulated conditionally within the same agreement.
The doctrine is especially relevant when the tax settlement derives from an inspection on corporate operations, business reorganizations or international structures, areas in which different legal classifications of the same operation may coexist.
At Resitax, a tax law firm in Mallorca, we analyze these types of procedures from a technical and strategic perspective. When you receive a particularly complex tax assessment, we review not only the amount owed, but also the consistency of its legal basis and the guarantees the tax authorities have used to justify the assessment.
The case examined in STS 3035/2026
The case analyzed originates from a declaration of fraud of law issued by the Inspection regarding a corporate operation linked to the liquidation of a foreign company integrated into a business group.
The settlement agreement did not limit itself to basing the regularization on said declaration of fraud of law, but incorporated, on a subsidiary basis and conditional upon that declaration being subsequently annulled, a second basis based on the ordinary valuation rules of the then current Consolidated Text of the Corporate Income Tax Law.
Having had the declaration of fraud of law annulled through economic-administrative proceedings, the Administration sought to maintain the tax debt based on the previously incorporated subsidiary ground.
It is precisely this use of two different legal grounds within the same tax settlement that is the issue being analyzed by the Supreme Court.
The Supreme Court's criteria on tax settlement
The High Court considers that this way of proceeding is incompatible with the taxpayer's right to defense.
It argues that a settlement cannot rest simultaneously on two mutually exclusive legal premises—on the one hand, the existence of fraud of law; on the other, its non-existence—insofar as this prevents knowing with certainty what the true basis of the administrative act is and against what the defense should be articulated.
The issue is especially relevant from the point of view of the motivation for the tax settlement.
The taxpayer must be able to know precisely what legal basis is used by the Administration to demand a certain debt and to structure their allegations and appeals against that specific basis.
When two incompatible qualifications are incorporated within the same act, that capacity for defense may be compromised.
STS 3035/2026 does not eliminate the double shot doctrine
The Court clarifies that this conclusion does not affect the so-called double-shot doctrine, under which the Administration may, within the legally established limits and deadlines, issue a new assessment after the annulment of the previous one.
What the ruling excludes is that such an eventuality be resolved preventively within the initial agreement itself, through the early incorporation of an alternative basis conditioned on the outcome of a future appeal.
The distinction is important.
It is not asserted that all new tax assessments issued after the annulment of previous ones are necessarily prohibited. What is being questioned is the use, within the same act, of two incompatible justifications intended to preemptively maintain the regularization regardless of the outcome of a subsequent review.
The ruling also emphasizes that it is not up to the Inspection to unilaterally define the legal effects of its own unlawful acts in a way that favors its interests, which links the adopted criterion to the principle of objectivity that governs the actions of the Administration in accordance with Article 103 of the Constitution.
Practical relevance of the doctrine for a tax settlement
The ruling provides a defense criterion applicable to any verification procedure in which the motivation of the settlement agreement combines, directly or subsidiarily, legal qualifications that are incompatible with each other.
This can occur, for example, when the Administration detects fraud or simulation and, at the same time, incorporates an alternative regularization based on ordinary valuation rules.
In such cases, the established doctrine allows questioning the validity of the act due to lack of defense, regardless of the substantive analysis that corresponds to each of the arguments used.
Therefore, when you receive a large tax assessment , it is advisable not to limit the review to the calculation made by the Tax Office
The following should also be studied:
- What is the main legal basis for the regularization?
- if subsidiary arguments exist;
- if both foundations are compatible;
- what facts support each rating;
- if you have been able to defend yourself against all of them;
- and what effect the doctrine established by the Supreme Court may have on the validity of the act.
Of particular importance to entrepreneurs and corporate groups
STS 3035/2026 may acquire special relevance in tax procedures related to complex business operations.
Among other scenarios, it may be necessary to review a tax assessment when it affects:
- corporate reorganizations;
- holding companies;
- intragroup operations;
- transfers or contributions of shares;
- company liquidations;
- related-party transactions;
- parent companies and subsidiaries;
- international structures;
- or application of anti-abuse rules.
In these types of proceedings, the amount of the regularization can be significant and the legal controversy can extend far beyond a mere discrepancy in calculation.
At Resitax we analyze both the economic structure of the operation and the reasoning used by the Inspection to determine if the settlement presents points of contention that should be incorporated into the defense strategy.
Considerations for clients with cross-border interests
This doctrine is particularly relevant for clients with international corporate structures, business reorganizations or operations linked to foreign parent companies or subsidiaries, cases in which the Inspection frequently resorts to the classification of fraud of law or simulation as the basis for regularization.
When a transaction affects several jurisdictions, the analysis of a tax settlement may also require reviewing the corporate structure, the economic function of the entities involved, and the tax treatment applied to each transaction.
For business owners, investors, and family groups with interests outside of Spain, these checks can affect asset and business decisions of particular economic importance.
From Mallorca, at Resitax we advise national and international clients who need to integrate defense against the Tax Office within a global vision of their business and asset structure.
Application to the special regime for posted workers
The ruling is also of interest in the field of checks relating to the special regime for workers posted to Spanish territory —article 93 LIRPF— when the Administration questions the economic substance of the employing company or the concurrence of the requirements for access to the regime.
In these cases, the incorporation of alternative and conditional grounds within the same settlement agreement is now exposed to a more solid challenge of nullity.
For taxpayers relocated to Spain with high salaries, managerial responsibilities, corporate holdings or international business structures, this issue can have considerable economic importance.
Therefore, when we review these procedures at Resitax, we jointly analyze the application of the special regime, the legal structure used, and the specific motivation of the Administration.
What to check if you have already received a tax assessment
Clients who have an ongoing inspection procedure, or who have received a tax assessment that includes this alternative motivation technique, should submit the agreement to a specific review in light of this criterion, given the effect it may have on the validity of the act and on the most appropriate appeal strategy.
At Resitail, when performing a procedure of this nature, we conduct a systematic review:
- Background of the inspection procedure.
- The operations subject to verification.
- The legal classification made by the Inspection.
- The motivation for the settlement agreement.
- The existence of primary and subsidiary foundations.
- The legal compatibility between them.
- The allegations made during the procedure.
- The possible existence of defenselessness.
- The quantification of the debt.
- The most appropriate challenge strategy.
Our goal is for you to know exactly what you are discussing with the Administration before deciding on the next step.
Resitax: specialized tax advice in Mallorca
At Resitax, we advise entrepreneurs, investors, family groups, and clients with national and international structures on particularly complex tax procedures, based in Mallorca.
When an inspection affects corporate operations, business holdings, international structures or relevant assets, we understand that the defense should not be limited to responding to each request in isolation.
We analyzed the file as a whole, the economic logic of the operations and the justification used by the Administration.
Our intention is to consolidate Resitax as a leading tax firm in Mallorca for clients who need rigorous technical advice before the Tax Office and a real understanding of the business and asset implications of each decision.
We do not start from the premise that every liquidation must be appealed.
First, we study the act, the background, and the documentation to determine what arguments exist, what their scope is, and what strategy is legally most appropriate.
Frequently asked questions about STS 3035/2026 and tax settlement
What does STS 3035/2026 establish?
The Supreme Court establishes that it is not possible to simultaneously base, within the same administrative act and in the terms examined by the judgment, the origin of a debt on a declaration of fraud of law and on the foreseeable nullity of that same declaration.
Can the tax authorities use two different arguments in a tax assessment?
The ruling does not mean that any subsidiary argument is invalid. The determining issue is whether the grounds used are legally incompatible and whether their use affects the taxpayer's right to a defense.
Does the ruling eliminate the double-shot doctrine?
No. The Supreme Court itself distinguishes the analyzed case from the possibility that the Administration may issue a new settlement after the annulment of another, within the limits and deadlines legally provided.
Why is the right to defense important?
Because the taxpayer must know with certainty what the true basis of the regularization is in order to decide which facts and legal arguments to base their defense on.
Could this ruling affect international transactions?
It may be relevant when the Inspection uses alternative legal classifications regarding business reorganizations, foreign companies, parent companies, subsidiaries or other cross-border operations.
Is it relevant to an inspection regarding the Beckham Law?
The doctrine may be of interest in checks of the regime of article 93 LIRPF when the Administration uses alternative and incompatible grounds to question access to or maintenance of the regime.
What should you do if you receive a large tax assessment?
Before deciding whether to accept or challenge the act, it is advisable to review both its quantification and the legal motivation, the previous inspection actions, the possible subsidiary grounds and the deadlines available to appeal.
Can Resitax review a tax assessment in Mallorca?
Yes. At Resitax, we analyze complex tax inspection procedures and settlements for entrepreneurs, investors, family groups, and clients with national and international interests, based in Mallorca.
Conclusion
The judgment of July 7, 2026 (STS 3035/2026, ECLI:ES:TS:2026:3035, rapporteur Mr. Navarro Sanchis) establishes a relevant criterion on the limits of administrative motivation when the same regularization is based on incompatible legal grounds.
The doctrine reinforces the need to review a tax assessment not only from an economic point of view, but also from the internal coherence of the reasoning used by the Tax Authorities and from respect for the right to defense.
The issue becomes especially important when corporate operations, business reorganizations, international structures or highly complex assets are at stake.
If you have an ongoing inspection procedure or have received a settlement that uses alternative legal grounds, at Resitax we can review the agreement and assess its impact on your defense strategy.
From Mallorca, we work with clients who require a technically rigorous tax response adapted to business and asset operations of special economic relevance.