Interview: UK Supreme Court Justice Lord Kitchin

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Interview: UK Supreme Court Justice Lord Kitchin

In an exclusive interview with Patent Strategy, UK Supreme Court Justice Lord Kitchin discusses the future of UK IP law, AI, Actavis v Icos, and whether he chats to his fellow judges on Whatsapp



Arriving on what was the hottest July day ever recorded, Justice of the UK Supreme Court David Kitchin very kindly invited us into his air conditioned office and then promptly asks if we would like a cup of tea. Naturally, we accepted. It’s never too hot for tea in London.


Lord Kitchin begins his conversation with us by looking ahead.

“I certainly hope I will be invited to participate in the IP appeals cases,” he says with a gentle hint of enthusiasm. “But I should say that doesn’t mean my view will carry the day.

“All of us on the panel engage in the issues and how they are decided, and this is extremely important. This can be valuable because they can bring perspective the others haven’t got.” His humility is as refreshing as his air conditioning.

“There is a case coming up on FRAND that I cannot participate in,” he notes, stirring his tea.

He is of course referring to Unwired Planet v Huawei, for which he wrote the Court of Appeal judgment before his elevation to the Supreme Court. Intrigued, given his expertise on the subject, we press him on to what extent his participation is forbidden.

Looking up from his cup, an eyebrow arches above his glasses, he adds: “No. I’m completely excluded. I’ll be aware it is going on, but nobody will discuss it with me.”

As the only justice with a background in IP, Lord Kitchin has a deep knowledge of technology, with a keen interest in the advancements of artificial intelligence. He acknowledges that for many businesses, IP can be the most valuable asset.

“Innovative technologies is an exciting area to work in, but it also comes with a high level of responsibility. We as judges must stay tuned in to developments and make sure our judgments are clear and coherent,” he says.

Lord Kitchin actively reads decisions from judges in different jurisdictions. He admits that reading rulings issued by foreign courts can help judges at the Supreme Court come to an agreement on very difficult cases.

“We do read with care and interest decisions written by other judges, and attach particular weight to decisions of the technical boards of the EPO and Enlarged Boards of Appeal. All of that interchange is enormously valuable.”

Actavis v Icos

Before rising to the bench of the Supreme Court, Kitchin issued another important IP ruling at the Court of Appeal that reversed a finding of obviousness in Actavis v Icos, a case involving the erectile dysfunction drug tadalafil.

The UK Supreme Court upheld this decision in March 2019.

“Now, I think it is right to say the decision we gave in the Court of Appeal was seen as a little controversial,” says Kitchin.

“Some said it changed the goal posts in terms of obviousness and reasonable expectations of success, which are two of the approaches that can be used to assess whether or not a patent is obvious. I do not see it that way at all,” he adds.

Tadalafil, sold under the brand name Cialis, was first discovered to be effective at a relatively high dose that could be taken when the need arises. Icos later discovered a dose of 5mg had minimal side effects and can be taken once a day instead of on the unpredictable occasion of necessity.

The Court of Appeal ruled the patent was obvious because a skilled team would have conducted dose studies, and even though they initially discovered the therapeutic plateau, the team would "very likely" carry on experimenting and eventually arrive at the invention. 

Furthermore, the team would get to the invention irrespective of which particular route they took. 

“These are the findings that led us in the Court of Appeal to find that the patent was obvious because it made those factual findings,” he says.

Lord Kitchin would like it known for the record that his ruling does not make it impossible to protect inventions related to dosage regimen forms. Nor does it mean it is impossible to have selection inventions in this area: “On the facts of this particular case and the findings Birss made, we decided this disclosure was not inventive.”

Decision making

Reaching a decision at court is no easy process. The Justices at the Supreme Court regularly meet to discuss cases in depth before reaching a conclusion.

“Every justice expresses a view on each aspect of appeal, but that’s not the end of it,” says Kitchin. “We prepare drafts and circulate them, and those drafts are discussed and debated. A lot of that happens online.”

“You mean y’all use a group chat in Whatsapp?” we ask playfully.

“No, not Whatsapp,” Kitchin says firmly. “Emails.”

Writing a judgment at the Supreme Court is a long process involving a lot more than listening to arguments in court and exchanging scholarly emails with colleagues.

Justices prepare and circulate drafts among themselves, and submit judgments to law reporters for editorial corrections before submitting them to counsel for any typographical corrections.

With that, we finish our tea and bid Lord Kitchin a farewell as we brace ourselves for the temperatures outside on the UK’s hottest day. Soon Lord Kitchin will be able to rule on IP cases that he didn’t decide on at the Court of Appeal – and we’ll likely be back for another cup to pick his brain when that happens.

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