A Constitutional Limit on Provincial Taxing Power – Barreiro

A Constitutional Limit on Provincial Taxing Power: The Prohibition on Discriminating Against Interjurisdictional Commerce in the Calculation of the Gross Income Tax Base

1. Summary

The Supreme Court of Justice of Argentina ruled in the case “YPF S.A. v. Province of Chubut re: declaratory action of certainty” (CSJ 57/2013 (49-Y)/CS1, decided April 23, 2026). The oil company challenged the Province of Chubut’s attempt to include in the taxable base of the Gross Income Tax (ISIB) the revenues derived from the export of hydrocarbon products extracted in Chubut but processed outside its territory — given that Chubut’s tax code exempts taxpayers from paying ISIB on amounts obtained through exports.

The Supreme Court declared the province’s tax claim unconstitutional, finding that the provincial tax authority’s conduct constituted fiscal discrimination against interprovincial commerce, analogous to an internal customs barrier prohibited by the Argentine Constitution.

The ruling establishes a significant precedent in interjurisdictional tax law by setting fiscal neutrality — with respect to where a taxpayer carries out intermediate stages of a single productive process — as an inviolable constitutional standard.

2. Background and Context

YPF brought a declaratory action for certainty against the Province of Chubut under Article 322 of the National Code of Civil and Commercial Procedure, seeking a ruling on the validity of the province’s tax position. That position, invoking Article 13 of the Multilateral Agreement, required the inclusion in the ISIB taxable base of revenues from the export of hydrocarbons extracted within its jurisdiction but processed outside it.

YPF explained that crude oil extracted from Chubut’s fields can have three destinations: (i) sale within Chubut itself; (ii) export directly from Chubut; and (iii) uninvoiced transfer to its refinery in La Plata, Province of Buenos Aires, where it is processed and subsequently sold — partly on the domestic market and partly for export. The dispute concerned the third scenario.

The central grounds for the challenge were: (i) violation of Article 75, Section 13 of the National Constitution; (ii) fiscal discrimination against interprovincial commerce; and (iii) horizontal double taxation, as the province was claiming a portion of taxes already paid in other jurisdictions for the same periods.

The Province of Chubut moved to dismiss the claim, arguing that it was not including export revenues in the tax base, but merely redistributing — in the exercise of its local taxing power — the taxable base as declared by the taxpayer itself. It contended that the deduction made by YPF — consisting of subtracting the portion of fuels and lubricants destined for export — had no basis in the Multilateral Agreement and “eroded the [taxable] base assigned to producing provinces, ultimately distorting the wellhead value attributed.”

3. Analysis of the Ruling

3.1. Constitutional Framework: The Commerce Clause and the Prohibition on Interjurisdictional Discrimination

The Court held that the Province of Chubut’s actions constituted fiscal discrimination against interprovincial commerce and, consequently, violated Articles 9 through 12 and Article 75, Section 13 of the National Constitution.

The Court recalled that those provisions establish a unified economic system throughout the national territory and preclude rules and acts by local authorities that increase the tax burden on interprovincial commerce relative to commerce conducted solely within the province. It reaffirmed the doctrine established in Fallos: 340:1480 (considerations 18–26), under which “provinces may not invoke territorial ownership to impose any obstacle whatsoever on activities that are substantively connected to interprovincial and international trade.”

3.2. The Principle of Fiscal Neutrality and Its Application to the Case

The defendant province itself acknowledged in its answer that export transactions involving petroleum — whether crude or processed — were not subject to the local ISIB (Article 122, Section 4, of the Provincial Tax Code). That exemption, the Court held, must apply regardless of where the intermediate stages of the productive process take place:

“If petroleum that is extracted, processed, and exported from Chubut is not included in the taxable base, then petroleum extracted in Chubut, processed wholly or partly in another province, and subsequently exported should not be included either” (consideration 5).

The province’s position implied the opposite: crude oil extracted in Chubut would be subject to ISIB solely because it had been processed in another province prior to export, whereas the same intermediate steps carried out within Chubut would generate no ISIB liability at all. That asymmetry is precisely the discrimination the Constitution prohibits and which the Court treated as analogous to an internal customs barrier.

4. Conclusion

The Supreme Court granted YPF’s claim and declared the Province of Chubut’s tax demand invalid.

The ruling confirms that the commerce clause of Article 75, Section 13 of the National Constitution, together with Articles 9 through 12 and Article 31, operates as an absolute check on the exercise of provincial taxing power, and that no sub-constitutional regime — including the Multilateral Agreement — can validate what the Constitution forbids.

Furthermore, taxpayers with productive processes spanning multiple jurisdictions — particularly those in the hydrocarbon, mining, and agro-industrial sectors — now have a clear standard of review: any interpretive construction of taxable base allocation regimes that results in a heavier tax burden on a taxpayer because it processes, stores, or industrializes goods outside the producing jurisdiction conflicts with the federal constitutional framework.

In other words, the ruling confirms that the principle of national economic unity operates as an operative limit — not merely a programmatic one — on local taxing power.

This decision constitutes a significant precedent in tax law and the constitutional limits on provincial taxing authority.

Its principal contribution lies in consolidating, with doctrinal clarity, that the prohibition on discriminating against interprovincial commerce is a self-executing constitutional mandate, operative independently of how special regulatory regimes may be interpreted.

For companies operating across multiple jurisdictions, the ruling reaffirms that a business decision to locate intermediate stages of a productive process in a jurisdiction other than the one where the raw material originates cannot serve as the triggering event for a tax that, had those same steps occurred within that jurisdiction, would never have arisen.