It had all the ingredients of a case HMRC would instinctively dislike.

A debt claim connected to the Lehman collapse. A Cayman seller. An Irish buyer. UK-source interest. A withholding tax refund claim. On the surface, it looked exactly like the sort of cross-border fact pattern that invites the familiar allegation: this may be technically clever, but surely it is really just treaty shopping.

That instinct is precisely why Burlington Loan Management DAC v HMRC [2026] EWCA Civ 461 matters. The Court of Appeal, in a judgment handed down on 20 April 2026, dismissed HMRC’s appeal and confirmed that the taxpayer was entitled to treaty relief from UK withholding tax on interest under the UK-Ireland treaty. In doing so, the court delivered a more important message than the refund itself: using a tax treaty is not, without more, an abuse of the treaty.

That is a point many international businesses and investors needed to hear.

The story behind the dispute

Burlington Loan Management DAC, or BLM, was an Irish-resident investment company engaged in acquiring and managing distressed debt. In the years following the financial crisis, it purchased claims in the secondary market against Lehman Brothers International (Europe). One of those claims had originally been held by SAAD Investments Company Limited, a Cayman-resident company. By the time BLM entered the picture, the principal had been paid and what remained was the right to future interest. BLM bought that interest-bearing claim at an arm’s-length price.

That commercial detail mattered.

Why? Because the seller, SICL, expected that it would suffer 20% UK withholding tax on the interest. A buyer with access to treaty relief could value the claim differently. BLM considered that, as an Irish-resident beneficial owner, it should fall within Article 12 of the UK-Ireland treaty and therefore receive the interest without UK withholding tax. HMRC disagreed. It argued that the anti-avoidance wording in Article 12(5) denied the relief because one of the main purposes of a person concerned with the assignment was to “take advantage” of the treaty article.

From a business perspective, HMRC’s argument had obvious appeal. If a claim becomes more valuable simply because the buyer can access treaty relief that the seller could not, does that not look like the treaty is being exploited?

The Court of Appeal said: not so fast.

The misconception the court rejected

The most important corporate lesson from Burlington is that obtaining a treaty benefit is not the same thing as abusing a treaty. The Court of Appeal held that the phrase “take advantage of” in Article 12(5) required more than merely obtaining the benefit of the article. In this context, it meant obtaining the benefit in a way that is contrary to the object and purpose of the treaty. That is a materially higher threshold than HMRC was inviting the court to apply.

That distinction is commercially significant.

Cross-border groups, credit funds, private capital investors and multinational treasury functions make decisions every day based on treaty outcomes. They price transactions by reference to withholding tax leakage, treaty access, local exemptions and creditability. If the mere fact that a purchaser expected a treaty benefit were enough to taint the arrangement, a large part of ordinary international commerce would become inherently suspect. Burlington pushes back against that logic.

Why Burlington won

The court did not say anti-abuse provisions are toothless. In fact, the judgment made clear that artificiality is not a formal prerequisite to treaty abuse, and a transaction does not become safe simply because it has a commercial label attached to it. But the court also recognised that genuine commercial context matters enormously. BLM was a long-established Irish-resident investor, acquiring distressed claims as part of its ordinary business, dealing with the seller at arm’s length, and acting as an independent third party rather than as a connected conduit. On those facts, the court considered BLM’s reliance on Article 12(1) to be entirely consistent with the object and purpose of the UK-Ireland treaty.

That last point deserves emphasis. The court was not impressed by the idea that one should start the analysis from the seller’s worse tax position and then infer abuse because the buyer was better placed. The more appropriate starting point was that the treaty expressly allocated taxing rights in favour of Ireland for an Irish-resident beneficial owner in BLM’s position. The fact that BLM expected to fall within that allocation did not, by itself, turn the transaction into a misuse of the treaty.

Why this matters beyond distressed debt

It would be a mistake to dismiss Burlington as a niche case about post-Lehman interest claims. The real significance is broader.

Many cross-border corporate structures depend on tax treaties to reduce or eliminate withholding taxes on interest, royalties or dividends. International groups routinely ask whether a financing platform, acquisition vehicle or investment company is making legitimate use of treaty protection, or whether HMRC may argue that the structure crosses the line into abuse. Burlington does not remove that risk. But it does offer a clearer framework: the key question is not whether the treaty benefit mattered commercially, but whether the way in which it was obtained ran contrary to the treaty’s object and purpose.

That is a more disciplined test, and for many commercially real structures it is a more reassuring one.

It also matters because advisers are increasingly dealing with purpose-based anti-avoidance language across the treaty network. Travers Smith notes that the Court of Appeal’s reasoning is likely to be relevant more broadly to purpose tests in international tax treaties, including treaties affected by the Multilateral Instrument. KPMG makes much the same point: although the exact wording in Burlington arose in the UK-Ireland treaty, the case has wider importance for how courts approach treaty purpose and abuse.

What businesses should actually take from the case

The practical lesson is not that “treaty shopping is fine”. That would be far too loose, and not what the court said.

The real lesson is more sophisticated. If a structure is commercially genuine, priced at arm’s length, and involves a real treaty-resident entity carrying on real activity of the kind one would expect in its business, then the fact that treaty relief is part of the economics is not automatically fatal. On the other hand, if the arrangement relies on weak substance, circularity, conduit features, non-arm’s-length pricing or a mismatch between legal form and commercial reality, Burlington will not save it. The judgment expressly leaves room for anti-abuse provisions to operate where the facts justify it.

That makes this a case about evidence as much as doctrine.

When groups are building cross-border financing or investment structures, they should be able to explain, calmly and coherently, why the relevant entity is there, what business it carries on, why the pricing works as it does, and why the treaty outcome is consistent with the purpose of the relevant treaty rather than a distortion of it. If they cannot do that, the technical analysis will eventually become uncomfortable.

The advisory point for 2026

In the current environment, that matters more than ever. Businesses are under pressure to simplify cross-border structures while still managing leakage, financing cost and investor returns. HMRC, meanwhile, remains alert to international arrangements that appear to generate tax-efficient outcomes. Burlington is therefore valuable not because it opens the door to aggressive planning, but because it confirms that commercially rational cross-border structuring is not inherently suspect simply because it produces a treaty benefit.

That is exactly the sort of nuance many boardrooms need.

If your group is using, or considering, an Irish or other treaty-resident vehicle for financing, debt acquisition, investment holding or broader cross-border structuring, this is an area where a careful review of substance, treaty entitlement and anti-abuse risk can make a material difference. For tailored advice, please contact Vectigalis Tax.

Website: vectigalistax.co.uk
Email: angelo@vectigalistax.co.uk

Burlington is a useful reminder that the right question in international tax is not whether a treaty benefit exists. It is whether the structure that secures it can withstand scrutiny when the commercial story and the legal analysis are read together.