Process: 316/2014-T

Date: October 20, 2014

Tax Type: IUC

Source: Original CAAD Decision

Summary

This arbitral tax decision (Process 316/2014-T) addresses a critical dispute regarding IUC (Unique Vehicle Circulation Tax) liability when vehicle ownership is not properly transferred in the registration system. The claimant company sold a vehicle in 2006, but the purchaser failed to register the ownership transfer. Subsequently, the Tax Authority assessed IUC for 2009-2012 (€1,887.00 plus €204.99 interest) against the claimant as the registered owner. The central legal controversy concerns the interpretation of Article 3(1) of the IUC Code, which states that taxable persons are vehicle owners, specifically 'those in whose names the vehicles are registered.' The claimant argues this provision establishes a rebuttable legal presumption under Article 73 of the General Tax Code, allowing proof of actual sale to defeat tax liability. The claimant submitted a sales invoice and requests for vehicle seizure to IMTT as evidence. Conversely, the Tax Authority contends Article 3(1) creates an irrebuttable legal fiction—not a mere presumption—meaning the registered owner remains liable regardless of actual ownership. The Authority argues the registration system must be determinative, and invoice evidence alone cannot override registration records. This case has significant implications for Portuguese taxpayers who sell vehicles but face continued tax liability due to buyers' failure to complete registration formalities. The arbitral tribunal must determine whether vehicle sellers can escape IUC liability through documentary proof of sale, or whether registration alone determines tax obligation. The decision impacts the interpretation of tax incidence rules, evidential standards in tax disputes, and the balance between registration formalities and economic reality in Portuguese tax law.

Full Decision

ARBITRAL DECISION

I. REPORT

A, commercial company with registered office in …, …, …, holder of the single registration and identification number for a legal person ..., represented by its liquidator B, hereinafter referred to as the Claimant, filed a request for the establishment of an arbitral tribunal in tax matters and a request for arbitral pronouncement, pursuant to the provisions of articles 2º no. 1 a) and 10º no. 1 a), both of Decree-Law no. 10/2011, of 20 January (Legal Framework of Arbitration in Tax Matters, hereinafter abbreviated as RJAT), requesting the annulment of 4 tax acts establishing the Unique Vehicle Circulation Tax (IUC) relating to the years 2009 to 2012, in the amount of € 1,887.00, and respective compensatory interest, in the amount of € 204.99.

To support its request, it alleges, in summary:

a) The Claimant was the owner of the vehicle with registration ...-...-...;

b) The vehicle referred to in a) was sold by the Claimant on 30.06.2006;

c) In the same transaction, the relevant vehicle sales declaration was issued and completed;

d) On 23.03.2009 and 02.01.2012, the Claimant submitted a request to IMTT for seizure of the vehicle in question, due to the fact that the vehicle's purchaser had not proceeded with the registration of the transfer of ownership;

e) The Claimant was notified, in its capacity as a taxable person for IUC purposes, of the assessments now in dispute;

f) The Claimant filed a gracious complaint against the tax acts establishing IUC and respective compensatory interest;

g) The gracious complaint filed was subject to a dismissal order;

h) The Claimant is not a taxable person for IUC purposes as it was not the owner of the vehicle at the date of occurrence of the taxable event;

i) All the assessments impugned relate to a vehicle alienated on a date prior to the occurrence of the taxable event;

j) Pursuant to article 3º of the CIUC, taxable persons for IUC purposes are the owners of the vehicles;

k) The presumption established in article 3º no. 1 of the CIUC is a rebuttable presumption;

l) Thus, the taxable person for IUC purposes is the owner, even if not registered in the vehicle register, provided sufficient proof is furnished to rebut the legal presumption arising from the registration.

The Claimant attached 5 documents and did not call any witnesses.

In the request for arbitral pronouncement, the Claimant chose not to appoint an arbitrator, whereby, pursuant to the provisions of article 6º no. 2 a) of the RJAT, the undersigned was appointed by the Deontological Council of the Administrative Arbitration Centre, the appointment having been accepted in the terms legally provided for.

The collective arbitral tribunal was constituted on 11 June 2014.

Notified in the terms and for the purposes of the provisions of article 17º of the RJAT, the Respondent filed a reply, alleging, in summary, the following:

a) Article 3º of the CIUC does not establish any presumption of ownership, but a true legal fiction – the legislator does not say they are presumed to be owners but that they are considered to be owners;

b) The failure to register changes in ownership in the register has the consequence that the obligation to pay IUC falls upon the registered owner, and the Tax Authority cannot assess tax on the basis of elements not contained in the register;

c) IUC is due by persons listed in the register as owners of the vehicles;

d) The invoice attached by the Claimant as proof of the conclusion of the purchase and sale contract is not capable of providing such proof.

The Respondent attached a copy of the administrative file and did not call any witnesses.

The meeting referred to in article 18º of the RJAT, as well as the production of oral and written submissions, was waived, without opposition from the parties, given the fact that, on the one hand, no matters susceptible to discussion at said meeting were raised and, on the other hand, the case contained all the documentary elements necessary and sufficient to decide the matter on the law.

II. SANITATION:

The Arbitral Tribunal was regularly constituted and is materially competent.

There are no nullities that invalidate the proceedings.

The parties possess legal capacity and standing and are legitimate, with no defects in representation.

There are no nullities, exceptions or preliminary questions that prevent the tribunal from considering the merits and which the tribunal must officially address.

III. QUESTIONS TO BE DECIDED:

The questions to be decided are as follows:

(i) To determine whether the rule of subjective incidence provided for in article 3º no. 1 of the CIUC provides for a rebuttable presumption or, conversely, a legal fiction, incapable of being rebutted by proof to the contrary;

(ii) To determine the legal value of the registration of motor vehicles;

(iii) To determine the probative value of the invoice attached by the Claimant.

IV) FACTUAL MATTERS:

a. FACTS PROVEN:

With relevance for the decision on the merits, the following factuality was proven:

a) The Claimant was notified of 4 assessments of IUC relating to the years 2009 to 2012, in the total amount of € 1,887.00 and respective compensatory interest, in the total amount of € 204.99;

b) The Claimant filed a gracious complaint against the tax acts establishing IUC and respective compensatory interest;

c) The gracious complaint filed was subject to a dismissal order;

d) On 23.03.2009 and 02.01.2012, the Claimant submitted a request to IMTT for seizure of the vehicle in question, alleging for this purpose that the vehicle's purchaser had not proceeded with the registration of the transfer of ownership;

e) The Claimant is registered in the vehicle register as the owner of the vehicle in relation to which the assessments now in dispute were issued;

f) The vehicle in question belongs to category C, referred to in article 4º of the CUIC;

g) The assessments now in dispute relate to a vehicle in relation to which, at the date of occurrence of the taxable event, an invoice of sale to a third party was issued by the Claimant, with the number, on the date of issue and value contained in document 2 attached with the initial claim, which is hereby given as fully reproduced.

b. FACTS NOT PROVEN:

With interest for the case, no other fact was proven.

c. SUBSTANTIATION OF FACTUAL MATTERS:

The conviction regarding the facts given as proven was based on the allegations made by the Respondent, not contradicted by the Claimant, as well as on the documentary evidence indicated in relation to each of the points, attached by the Claimant, the authenticity and correspondence to reality of which were not questioned by the Respondent.

V. LAW:

a. Interpretation of article 3º no. 1 of the CIUC:

The Claimant invokes that, with regard to the IUC assessments in dispute, the requirements for subjective incidence provided for in article 3º of the CIUC are not met, and it is not, therefore, a taxable person for IUC purposes.

For this purpose, it alleges, in summary, that article 3º of the CIUC establishes an implicit presumption of ownership of vehicles in favour of those in whose names the same are registered, a presumption that, by virtue of the application of the general rule provided for in article 73º of the General Tax Code, is rebuttable by proof to the contrary.

For its part, the Respondent contends that article 3º of the CIUC does not establish any implicit presumption, but a true legal fiction, which cannot be rebutted, therefore, by proof to the contrary.

Given the position of the parties, let us examine what, in accordance with the rules of legal interpretation enshrined in law, should be the correct interpretation of article 3º no. 1 of the CIUC.

Article 3º no. 1 of the CIUC provides:

"The taxable persons for the tax are the owners of the vehicles, being considered as such the natural or legal persons, of public or private law, in whose names the same are registered.

From a simple reading of number one of the aforementioned provision, it is clear, without great difficulty, that the crux lies in the expression 'considered as' used by the legislator.

Considering the terminology used, should it be understood that the legislator intended to establish an implicit presumption or a true legal fiction?

For the consideration of this question, it is important, first of all, to set out here some legal concepts and legal definitions.

Thus,

Pursuant to the provisions of article 349º of the Civil Code, presumptions are the inferences that the law or the judge draws from a known fact to establish an unknown fact.

With respect to legal presumptions, number 2 of article 350º of the same Code prescribes that these may be rebutted by proof to the contrary, except in cases where the law prohibits it.

As for presumptions of tax incidence, in concrete terms, article 73º of the General Tax Code establishes that these always admit proof to the contrary.

Beyond presumptions, the legislator also resorts to the so-called "legal fictions", which are translated as "a legal process that considers a situation or a fact as distinct from reality in order to attribute legal consequences to it"[1].

According to the thesis advanced by the Respondent, the fact that article 3º no. 1 of the CIUC establishes that they "are considered" as owners, rather than "are presumed" to be owners, reveals that the legislator, within its freedom of legislative form, expressly intended to determine that the persons in whose names the vehicles are registered are considered, without the admissibility of any proof to the contrary, to be the owners thereof.

Still in accordance with the Respondent, if the legislator intended to create a presumption and not a legal fiction, it would have written, as it does in several other diplomas, that they are presumed to be owners and not that they are considered to be owners.

From the outset, we may state that this tribunal does not endorse the understanding defended by the Respondent.

This is because, through the analysis of the historical and teleological elements, in addition, of course, to the literal element of legislative interpretation, we will necessarily arrive at the conclusion that the legislator did not intend to establish any legal fiction but only and solely a presumption, which can be rebutted by proof to the contrary in the terms and for the purposes of the provisions of article 73º of the General Tax Code.

Let us examine this:

As regards the historical element, it is important to note that the current IUC had its genesis in the creation, through Decree-Law 599/72, of 30 December, of a tax on vehicles.

This tax on vehicles, which remained in force until the creation of the current CIUC, expressly established that the tax is due by the owners of the vehicles, presumed as such the persons in whose names the same are registered or matriculated – see article 3º of the Regulations of the Tax on Vehicles, annexed to the aforementioned Decree-Law 599/72, of 30 December.

Upon the approval of the new CIUC, the legislator replaced the expression "presumed as such" with the expression "considered as such", but for this reason one cannot defend that such alteration signifies a true substitution of a presumption (rebuttable) by a legal fiction (irrebuttable).

This is because, as JORGE LOPES DE SOUSA teaches us[2], in matters of tax incidence, presumptions may be revealed by the expression "presumed" or by similar expression. By way of example, the author advances that in article 40º no. 1 of the CIRS the expression "presumed" is used, whereas in article 46º no. 2 of the same Code the expression "considered" is used, there being no difference between one expression and the other, both meaning, ultimately, the same: a legal presumption.

The same occurred with the CIUC in which, notwithstanding the expression "presumed" having been altered, in relation to the original wording, for the expression "considered", no substantive change was produced, with the different expressions having exactly the same meaning.

We arrive at the very same conclusion through the analysis of the teleological element.

In fact, it is important to bear in mind the explanatory statement of Bill no. 118/X of 07/03/2007, underlying Law no. 22-A/2007, of 29 June.

Upon examination of this explanatory statement, it is verified that what was intended was to undertake a "comprehensive and coherent reform of taxes linked to the acquisition and ownership of motor vehicles" which results from the "imperative necessity of bringing clarity and coherence to this area of the tax system and the necessity, even more imperative, of subordinating it to the principles and concerns of an environmental and energy nature that nowadays mark the discussion of motor vehicle taxation".

Continuing, the aforementioned explanatory statement explains that "the two new taxes which are now created, the tax on vehicles and the unique vehicle circulation tax, constitute much more than the technical continuation of the figures created in the 70s and 80s which preceded them, aimed predominantly at revenue raising, indifferent to the social cost resulting from motor vehicle circulation. They constitute something different, figures now of the century in which we live, with which it is certainly intended to raise public revenue, but to raise it in proportion to the cost that each individual causes to the community."

Which led, moreover, to the establishment of the principle of equivalence, inscribed in article 1º of the CIUC, "thus making it clear that the tax, as a whole, is subordinated to the idea that taxpayers should be burdened in proportion to the cost they cause to the environment and to the road network, this being the raison d'être of this tax figure. It is this principle that determines the burden on vehicles according to their respective ownership and up to the moment of scrapping".

IUC, as a true environmental tax, has, therefore, as taxable person the polluter, being nothing more, ultimately, than the establishment of the polluter-pays principle.

By which it is verified that the structuring principle of the reform of motor vehicle taxation is precisely the incidence of taxation on the true user of the vehicle, this principle not being consistent with the "blind" reading of the letter of the law, which could ultimately lead to taxing those who were not owners and, in this way, those who were not the subject causing the "environmental and road cost" caused by the vehicle, referred to in article 1º of the CIUC.

From all that has been set out, it results that the literal, historical and teleological elements of interpretation of the law necessarily lead to the conclusion that the expression "considered as" has exactly the same meaning as the expression "presumed", and should, therefore, be understood as establishing article 3º no. 1 of the CIUC a true presumption of ownership and not any fiction, and therefore such presumption is rebuttable.

Pursuant to the provisions of number 1 of article 3º of the CIUC, the taxable person for the tax is, in principle, the owner, since the law presumes that it is the owner who uses the asset. But if it is proven that, ultimately, it is not the owner who makes use of the vehicle, but a third party, then it will be this party, necessarily, the taxable person for the tax.

This, unless we are mistaken, is the interpretation that is in harmony, on the one hand, with the principle set out in article 11º no. 3 of the General Tax Code, that in cases of doubt about the interpretation of tax rules "account should be taken of the economic substance of the tax facts" and, on the other hand, with the principle of equality in the distribution of public charges, which requires that the taxation of the generality of taxpayers, whenever possible, be based on the economic reality underlying the tax facts[3].

Indeed, any other interpretation would violate, immediately, the aforementioned principle of equivalence established in article 1º of the CIUC, pursuant to which it is established that IUC seeks to "burden taxpayers in proportion to the environmental and road cost which they cause, in implementation of a general rule of tax equality".

b. The legal value of vehicle registration:

Pursuant to the provisions of number 1 of article 1º of Decree-Law 54/75, of 12 February, which instituted the Register of Motor Vehicle Property, "the registration of motor vehicles has essentially the purpose of giving publicity to the legal situation of motor vehicles and their trailers, with a view to the security of legal commerce".

For its part, article 7º of the Real Property Register Code, supplementary legislation of the vehicle register, prescribes that "definitive registration constitutes a presumption that the right exists and belongs to the registered holder, in the precise terms in which the registration defines it".

As is well known, the registration of property does not have a constitutive nature, but merely a declarative one, allowing only the registration to presume the existence of the right and its ownership. Note, presume, not fictionalise, which means that the presumption resulting from the register can be rebutted by proof to the contrary.

And this is so precisely because, pursuant to the provisions of article 408º of the Civil Code, subject to the exceptions provided for by law, the constitution or transfer of real rights over a determined thing is effected by mere effect of the contract, and its validity does not depend on registration in the register.

In the case of a contract for the purchase and sale of a motor vehicle, with the law providing no exception for it, the contract has real effect, with the purchaser becoming its owner, independently of the register.

Now, in the same way that the purchaser becomes the owner independently of the register, so the registered holder ceases to be the owner, although still appearing in the register as such.

Note that, in the present case, despite the lack of registration in the register, the transfer made is enforceable against the Respondent, despite the provisions of number 1 of article 5º of the Real Property Register Code, which provides that facts subject to registration only produce effects against third parties when registered.

This is because the Respondent is not, for the purposes of the provisions of this article, considered a third party for purposes of registration.

The notion of third parties for purposes of registration is established in number 4 of the same article 5º: third parties, for purposes of registration, are those who have acquired from a common author rights incompatible with each other, which is manifestly not the case in the present proceedings.

In the case of the present proceedings, the Claimant appears in the register as the owner of the vehicle which is the subject of the assessments in dispute, although the Claimant alleges that it was not, at the date of the taxable event, its owner, as it had already been alienated.

Since the presumption resulting from the register is, as we have seen, rebuttable, let us see whether the invoice attached by the Claimant is capable of rebutting such presumption.

c. On the probative value of the invoice attached by the Claimant:

With a view to proving that the vehicle whose assessments are the subject of the present proceedings was alienated on a date prior to the birth of the taxable event, the Claimant attached the respective sales invoice.

On this matter, the Respondent invoked that "invoices, by themselves, are not capable of proving the conclusion of a synallagmatic contract such as purchase and sale, since that document does not itself reveal an essential and unequivocal declaration of intention (i.e., acceptance) on the part of the alleged purchaser" (cf. article 71º of the reply).

Let us see whether the Respondent has reason regarding this invoked lack of probative value of the invoice attached by the Claimant.

As results from the facts proven, the vehicle in question in the present proceedings belongs to category C, referred to in article 4º of the CUIC, so that the taxable event occurs on the date of its respective registration or on each of its anniversaries.

It also follows from the facts proven that, at the date of occurrence of the taxable event, an invoice of sale to a third party had been issued by the Claimant.

The Respondent contends that the invoice is not a document suitable to prove the sale of the vehicle, being merely a unilaterally issued document by the Claimant, alleging that "there is no lack of cases of issuance of invoices relating to transfers of goods and/or provision of services that never came to pass" (cf. article 72º of the reply).

It is true, as the Respondent invokes, that there are many situations in which invoices do not evidence any legal transaction.

In the present case, however, no element permits us to conclude that the attached invoice does not evidence any transaction, and it is certain that its falsity was not even argued by the Respondent, which merely invoked that there exist several such situations, without specifically referring to the present case being subsumed into such a situation.

Therefore, in the absence of any elements or grounds that permit us to conclude to the contrary, we shall naturally have to accept the veracity of the attached document.

All the more so because, as is well known, the statements of taxpayers presented in accordance with the law and the data and calculations entered in their accounting or records enjoy a presumption of veracity and good faith, pursuant to the provisions of article 75º of the General Tax Code.

A presumption which, like the other presumptions analyzed in the present proceedings, is rebuttable by proof to the contrary, and it is certain that the Respondent failed to rebut this presumption (nor in fairness did it attempt to).

It must be noted here that the Claimant further invoked that, at the date of issuance of the invoice relating to the vehicle in question in the present proceedings, a purchase and sale declaration of the said vehicle was also issued and completed, a declaration allegedly attached with the initial request under number 3.

Although the Respondent did not call into question the veracity of this document, the fact is that, given the manifest lack of quality of the copy attached, the tribunal cannot confirm the content of the respective document, in particular for proof of what is alleged by the Respondent.

In fact, being the case, in the present instance, of proof that necessarily must be made by document, the illegibility of the same has as a consequence the impossibility of proof of the fact that one sought to prove with it.

For which reason this tribunal cannot, it is repeated, although the Respondent did not call this document into question, give as proven the issuance and completion of a purchase and sale declaration of the vehicle in question.

Having said this,

Accepting the veracity of the invoice attached by the Claimant, we shall have to consider, without the need for any other considerations, it to be a document capable of proving the alienation of the vehicle in question.

In fact, with the law not providing for any specific form for the conclusion of a contract for the purchase and sale of a movable asset, it shall necessarily have to be accepted as proof of the said contract the invoice issued in accordance with legal requirements.

By which it is verified that, at the date of occurrence of the taxable event (date of registration or each of its anniversaries) the Claimant had alienated the vehicle whose assessments were impugned, although the said alienation was not subject to registration in the register.

Thus, given the fact that, as has already been set out, the presumption resulting from the register is rebuttable by proof to the contrary, proof that is considered sufficient with the presentation of the sales invoice of the vehicle, it is verified that, with respect to this vehicle, the Claimant is not its owner and is therefore not a taxable person for the IUC assessed.

VI. OPERATIVE PART:

In view of the foregoing, judgment is rendered upholding the claim for declaration of illegality of the 4 IUC assessment acts relating to the years 2009, 2010, 2011 and 2012, in the amount of € 1,887.00, as well as the respective compensatory interest, in the total amount of € 204.99, with all legal consequences.

The value of the case is fixed at € 2,091.99, pursuant to article 97º-A no. 1 a) of the Tax Code of Procedure and Process, applicable by force of subparagraphs a) and b) of no. 1 of article 29º of the RJAT and no. 2 of article 3º of the Regulation of Costs in Tax Arbitration Proceedings.

The arbitration fee is fixed at € 612.00, by application of Table I of the Regulation of Costs in Tax Arbitration Proceedings, pursuant to the provisions of articles 12º no. 2 and 22º no. 4, both of the RJAT, and article 4º no. 4 of the aforementioned Regulation, to be paid by the Respondent, as the losing party.

Register and notify.

Lisbon, 20 October 2014.

The Arbitrator,

Alberto Amorim Pereira

Text prepared by computer, pursuant to no. 5 of article 131º of the CPC, applicable by referral of subparagraph e) of no. 1 of article 29º of Decree-Law 10/2011, of 20/01.

The drafting of this decision is governed by the old spelling.

[1] FRANCISCO RODRIGUES PARDAL, "The use of presumptions in tax law", in Ciência e Técnica Fiscal, no. 325-327, page 20.

[2] In "Tax Code of Procedure and Process Annotated and Commented", Volume I, 6th Edition, Áreas Editora, Lisbon, 2011, page 589.

[3] JORGE LOPES DE SOUSA, op. cit., pp. 590 et seq.

Frequently Asked Questions

Automatically Created

Who is the taxable person for IUC when a vehicle has been sold but the registration was not transferred?
Under Article 3(1) of the IUC Code, the taxable person is the individual or entity in whose name the vehicle is registered. When a vehicle is sold but registration is not transferred, the case presents a fundamental dispute: the Tax Authority maintains that the registered owner remains liable for IUC regardless of actual sale, treating registration as determinative through a legal fiction. However, the claimant argues that registration creates only a rebuttable presumption under Article 73 of the General Tax Code, allowing the actual seller to prove they transferred ownership and escape liability. The arbitral tribunal must resolve whether registration is conclusive or merely presumptive of tax liability.
Can the legal presumption of vehicle ownership under Article 3 of the IUC Code be rebutted by the taxpayer?
This is the core legal issue in the case. The claimant contends that Article 3(1) of the IUC Code establishes an implicit rebuttable presumption of ownership favoring registered owners, which can be overcome by contrary proof under Article 73 of the General Tax Code. The seller argues that documentary evidence of sale (such as invoices and seizure requests) should suffice to rebut the presumption. However, the Tax Authority argues that Article 3(1) creates an irrebuttable legal fiction—the provision states owners 'are considered as such' those registered, not that they are 'presumed' to be owners. Under this interpretation, registration definitively determines IUC liability without possibility of rebuttal, ensuring administrative certainty and preventing taxpayers from challenging assessments based on unregistered transactions.
What evidence is required to prove vehicle sale and rebut the IUC ownership presumption?
The claimant submitted a sales invoice as primary evidence of the vehicle transfer, along with two requests to IMTT for vehicle seizure (dated March 23, 2009, and January 2, 2012) due to the buyer's failure to register ownership transfer. However, the Tax Authority challenged the probative value of the invoice, arguing it cannot overcome registration records. The arbitral tribunal identified three key issues: (i) whether Article 3(1) allows rebuttal at all, (ii) the legal value of motor vehicle registration, and (iii) the specific probative weight of the submitted invoice. If registration creates only a rebuttable presumption, sellers would need clear documentary proof of sale, proper notification to authorities, and possibly evidence that the buyer took possession and control. The case highlights the evidentiary burden on sellers seeking to escape IUC liability.
What is the difference between a legal presumption and a legal fiction in Portuguese tax law regarding IUC?
This distinction is central to the case's resolution. A legal presumption is a rebuttable inference that certain facts exist based on proven circumstances; it can be overcome by sufficient contrary evidence. Under Article 73 of the General Tax Code, tax presumptions are generally rebuttable unless law specifies otherwise. The claimant argues Article 3(1) creates such a presumption—registration suggests ownership but doesn't conclusively prove it. Conversely, a legal fiction is an irrebuttable legal construct where the law deems something to be true regardless of actual facts. The Tax Authority argues Article 3(1) uses operative language ('are considered as such') establishing a fiction: registered persons are treated as owners for IUC purposes without exception. This interpretation prioritizes administrative efficiency and registration system integrity over economic reality, preventing taxpayers from challenging assessments based on unregistered transactions.
What remedies are available to challenge IUC tax assessments on vehicles already sold in Portugal?
Portuguese taxpayers challenging IUC assessments on sold vehicles have several remedial options. First, they may file a gracious complaint (reclamação graciosa) with the Tax Authority, as the claimant did here, though this was dismissed. Second, they may request judicial review through administrative courts. Third, they may initiate arbitration proceedings under the Legal Framework of Arbitration in Tax Matters (RJAT, Decree-Law 10/2011), as occurred in this case, which provides a faster alternative to judicial litigation. Taxpayers should also proactively request vehicle seizure from IMTT when buyers fail to register transfers, documenting their diligence. The case demonstrates that while remedies exist, success depends on whether tribunals interpret Article 3(1) as creating a rebuttable presumption or irrebuttable fiction. Preventive measures include contractually obligating buyers to complete registration promptly and maintaining comprehensive documentation of all vehicle transfers to support potential challenges to tax assessments.