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PRACTICE AREA

International
Tax Disputes

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Transfer pricing, MAP procedures, withholding tax recovery, treaty interpretation, and proceedings before tax authorities across multiple jurisdictions.

International tax disputes follow predictable triggers: transfer pricing adjustments, characterisation of cross-border payments, residency conflicts, denial of treaty benefits, and challenges to substance under anti-abuse rules. Each trigger plays out before different authorities and through different procedural routes.
VLO acts in tax controversy with focus on multi-jurisdictional matters where multiple tax authorities have competing claims on the same income or where treaty-based recovery is available but not being granted. We litigate directly before Portuguese tax authorities; we coordinate proceedings in other jurisdictions through specialist local counsel.
Typical engagement length: 12–48 months including litigation phases. Matter values typically €500K–€50M+ in disputed tax.
QUICK INQUIRY
WHAT WE DO
Send a brief for this practice
Cross-border tax controversy
WHEN CLIENTS COME TO US
Three common scenarios

TRANSFER PRICING ADJUSTMENT

Tax authority has issued an adjustment that creates double taxation. You need a treaty-based recovery procedure combined with domestic challenge strategy.
WITHHOLDING TAX DENIED
A treaty rate is being denied on intercompany payments. You need recovery strategy through administrative and court procedures.
SUBSTANCE CHALLENGE
Anti-abuse rules are being invoked against your holding structure. You need a defence strategy that holds across multiple jurisdictions where the structure operates.
OUR APPROACH
Engagement methodology

SCOPING

Identify all jurisdictions and forums involved

STRATEGY MEMO

Procedural map, merits, fees — 5 business days.

EXECUTION

Local counsel coordinated by VLO partner

RESOLUTION

Settlement, award, or judgment — coordinated.

WHY VLO
Differentiators for this practice
PARTNER OWNERSHIP
One named partner stays on the matter from first call to final outcome. No reassignment, no transition meetings.
Local counsel managed by VLO — clients receive one consolidated reporting in English, not separate bills from multiple firms.
CROSS-BORDER COORDINATION
TRANSPARENT FEES
Fixed-fee, capped, or hourly with monthly caps — chosen at engagement. No surprises in billing.
No press without explicit consent. Confidential by default. Enhanced communications encryption.
DISCRETION
REPRESENTATIVE WORK
Selected practice areas in action.
Examples illustrate the type of matter VLO handles in this practice. Specifics are withheld for confidentiality.
TAX
Transfer pricing dispute
Acted for taxpayer in dispute over benchmarking methodology; favourable arbitration ruling.
TAX
Bilateral procedure
Coordinated treaty-based procedure between competent authorities; double taxation eliminated.
TAX
Withholding recovery
Treaty-based recovery of withholding tax denied at source on cross-border dividends.
LEAD PARTNERS FOR THIS PRACTICE
ADJACENT PRACTICES
Often combined with
CORPORATE DISPUTES
When tax dispute affects shareholder positions.
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When tax dispute requires court proceedings.
LITIGATION
M&A
When transaction tax positions are challenged.
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FREQUENTLY ASKED
Common questions
Can you act before tax authorities outside Portugal?
Directly in Portuguese tax authority proceedings. In other jurisdictions, we coordinate with specialist tax counsel. Bilateral treaty procedures require dual representation in both treaty jurisdictions.

Yes — VAT disputes with cross-border component (place of supply, intra-EU rules, reverse charge mechanisms). Pure domestic VAT we typically refer to specialist tax counsel.
Do you handle VAT disputes?
What is your fee structure?
Hourly with monthly caps for litigation phases. Success-fee components considered for refund cases. Fixed-fee for technical memos and treaty procedure filings.
Treaty procedure eliminates economic double taxation through agreement between competent authorities. Litigation goes through domestic courts and may not address the foreign-side adjustment. We typically pursue both in parallel.
How does a treaty-based procedure compare to litigation?
WE ARE TYPICALLY ENGAGED BY
Who comes to VLO
GENERAL COUNSEL & CHIEF LEGAL OFFICERS
Of European, MENA, and CIS-linked industrial groups facing a cross-border dispute that cannot be resolved within their existing panel. We are typically called when the matter spans more than two jurisdictions or where local counsel coordination has stalled.
CFOs & CHIEF FINANCIAL OFFICERS
Of cross-border PE sponsors and family-owned holdings. Engagement triggers: post-closing earn-out disputes, FDI screening for non-EU buyers, tax controversy with international dimension.
HEADS OF SPECIAL SITUATIONS
At credit funds, banks, and institutional creditors pursuing recovery against layered debtor structures. We coordinate parallel enforcement campaigns across multiple jurisdictions as a single integrated mandate.
FAMILY OFFICES & PRIVATE PRINCIPALS
With multi-jurisdictional structures and disputes that require discretion alongside technical complexity. Our boutique model, partner-led engagement, and standing confidentiality protocols make this a natural fit.
Have a tax dispute?
Send the brief — we respond within one business day.
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