So, can you patent software? And other myths about software patents

Iain Russell shares several software patent myths he still hears today, where each comes from, and how they compare with reality, including what the Supreme Court’s decision in Emotional Perception has changed.

As a patent attorney who has worked on software inventions for over twenty years, I’ve heard many myths about software patents. In this article, I’ve set out some of the most common ones I still encounter. There is usually a reason a myth persists, so rather than dismissing each one as a simple misunderstanding, I’ve tried to explain where I think it comes from then set out the reality.

Myth 1: “You can’t patent software”

This is, without doubt, the myth I encounter most often. So where does it come from?

UK and European patent legislation states that programs for computers are not inventions. However, there is a qualifying statement: the exclusion applies only to the extent that the invention relates to a program for a computer “as such”. Those two words have been at the centre of debate and discussion in the UK and across Europe for fifty years.

In reality, it is possible to patent software-based inventions (often known as computer-implemented inventions, or CIIs) in the UK and Europe. I’ve been doing it my whole career. Some types of software innovation are clearly patentable, some are clearly not, but there’s also a large grey area between those extremes.

Ultimately, the UK and European patent offices are looking to see whether an invention solves a technical problem in a novel and non-obvious technical manner. That’s a simplification of the law and practice, but it serves as a reasonable shorthand definition.

So, what is “technical”, and what is not? There’s no precise definition and, as you might expect, that’s where most of the uncertainty lies. When I speak to inventors and applicants, I often suggest equating the term “technical” with computer science or computer engineering. Problems such as reduced latency, more efficient hardware usage, or greater computational accuracy are more likely to be considered technical than “it makes more money” or “it looks nice”.

Even with my experience, it can sometimes be difficult to provide a firm indication of whether a patent application will meet these requirements when examined (and that’s  without considering Patent Office inconsistency and subjectivity). But sometimes an invention that initially appears non-technical because of how it’s presented by the inventor or applicant reveals interesting technical details through further probing. This is why an experienced specialist can be a valuable sounding board early in the process.

The European patent law position on software inventions has been relatively stable for many years. The UK position changed recently, following the Supreme Court’s decision in Emotional Perception AI Limited v Comptroller General of Patents, Designs and Trade Marks [2026] UKSC 3. Fully explaining the ramifications of that decision would take an entire article, but briefly, the Supreme Court found that the approach set out in Aerotel Ltd v Telco Holdings Ltd [2006] EWCA Civ 1371 and previously adopted in the UK was incorrect. The Supreme Court found the Aerotel test to be overly strict, and decided that UK law and practice should align more closely with the European position.

We’re still in the early days of seeing how the UK Intellectual Property Office (IPO) applies Emotional Perception. However, one positive change is already clear: the IPO’s former practice of not even searching inventions it considered non-technical has generally been replaced by those inventions being searched, albeit  objections based on non-technical subject matter are still being raised. Even this limited change is welcome, as it’s always helpful to have a clearer understanding of the prior art the IPO considers close to the invention.

Myth 2: “Copyright protects software, so you don’t need to think about patents”

I think the origin of this myth  is twofold. Copyright does indeed provide some protection for software while there is also the perception that software is not patentable, as discussed above. But the protection copyright provides is limited and very specific. For example, it covers the underlying code, certain graphics, or other creative works within and associated with the software. It doesn’t protect the underlying functionality, or an abstraction of those creative works. This is where patents differ. Patents are focused more on functionality, and on higher-level innovation, than on the specific code by which the software runs.

Infringing copyright also requires some form of copying, so in theory there is a defence if someone can show they developed software independently. Patents, on the other hand, are a monopoly right and do not require someone to have copied the invention to infringe. 

Myth 3: “There’s no point in having a software patent if we can’t afford to enforce it”

This myth combines the idea that patents are only useful for offensive purposes with the reality that enforcing them can be very expensive. However, there are several other benefits to obtaining a patent, including a software patent, that are often overlooked.

One is the Patent Box corporation tax discount. At a very general level, a company paying UK corporation tax can pay a reduced rate (currently an effective 10%, against the 25% main rate) on profits it makes from a patented invention. The complexities go well beyond the scope of this article, but the financial benefit is real, and plenty of businesses are simply unaware of it. With Patent Box, a software patent could save a company much more money than it costs to get the patent.

While it’s generally desirable to maximise the valid scope of a granted patent (to catch as much infringement as possible), a very narrow patent may still be enough to gain Patent Box benefit, as long as it covers an invention on which profit is being made. A narrower patent is often easier and less expensive to obtain than a broader one. Given the challenges around software patentability, pursuing narrower scope in a patent application may provide a simpler and cheaper route to getting the patent granted.

There’s also a marketing and deterrent effect. Being able to say “patent pending” or “patented” carries weight in itself. Third parties may see a patent application or patent and quietly take evasive action. The existence of a patent application or patent may prompt a competitor to steer clear without the patentee even knowing the competitor has done so, let alone having to enforce anything.

Myth 4: “I’d have to disclose the underlying code”

The origin of this myth may be the requirement in patent law that a patent must provide an enabling disclosure of the invention. This means that a skilled person must be able to work the invention from the patent application alone, without having to invent any part of it themselves. It is understandable that someone might think this requires the underlying code itself to be disclosed for a software invention. In fact, it isn’t even necessary for the code to have been written when a software patent application is filed.

In reality, it’s almost never necessary to disclose underlying code and we rarely do. Occasionally, we might include a code snippet or a few lines of pseudo code, but this is always a judgment call. As mentioned above, software patent applications tend to focus on functionality, and an enabling disclosure can often be provided by explaining that functionality without giving specific code. It’s rare that the code itself is where the clever (and, hopefully, patentable) aspects of a software invention lie. It’s therefore usually sufficient to describe operation of the software with reference to simple flowcharts and/or block diagrams, where the software components or modules are represented by functional blocks linked by arrows.

In fact, not only is source code disclosure typically not required, there’s a good commercial reason for not including it in a patent application. If a patent application is pursued for long enough, its content is published. Any source code in a published patent application is therefore visible to your competitors. Worse, the publication stays available even if no patent is ultimately granted. Since source code is rarely required and rarely boosts patentability, it seldom makes sense to include it in a patent application.

Myth 5: “The product is selling well, so I should now think about patenting, right?”

Another common myth is that you can test a product in the market and then safely apply for a patent if it proves successful.

The most likely origin of this myth is that some patent systems have a so-called grace period, in which certain earlier disclosures are effectively ignored when assessing the validity of a later-filed patent application. The US grace period, in particular, is quite well known so perhaps there is a perception that such grace periods apply more generally as a result. However, many countries’ patent systems have no such provision. Even where such grace periods do exist, they come with limitations and complexities that can significantly limit their use.

In practice, a very high-level disclosure of an invention’s function typically won’t anticipate a later-filed patent application for a specific software-based control system that provides the technical improvements that implement that function. For example, if you publish an article that says “we’ve found a way to make coffee bean roasting more energy efficient” without any technical explanation of how that outcome is achieved, that article typically won’t anticipate a later patent application you file directed to a clever and specific software-based control system that optimises various components of a coffee roasting machine towards that goal.

Not all situations are as straightforward as this example. If any non-confidential disclosure is contemplated before a patent application is filed, seek advice from a patent attorney first. If disclosure to a limited audience before filing is absolutely essential (such as  to an investor or a consultant being engaged to implement the invention), the risk may be managed. Put a strong confidentiality agreement in place with the party receiving the information, restrict what is to be disclosed to that party, and define in writing the nature of what is being disclosed.

Be aware that most patent systems apply an “absolute novelty” standard when deciding whether an invention in a patent application is novel (i.e. new). This means that any non-confidential disclosure before the effective filing date of a patent application can be used as prior art against it, restricting the scope of any subsequently granted patent or even blocking grant completely, depending on the disclosure details. Under the absolute novelty standard, the specific form of a disclosure is irrelevant. A page on the company’s website, an earlier published patent application, a scientific paper, a pitch deck shared with prospective investors without a non-disclosure agreement (NDA) in place, the public use or display of a device that allows an onlooker to deduce how the invention works (even if the invention is software running on the device) and so on, in any language, all count as prior art.

Finally, an independent disclosure by a third party before filing can also block the granting of a patent, or have a later impact on its validity. An applicant can manage their own disclosures but that does not stop someone else from publishing something similar, which could still prevent a patent being granted, or require the applicant to limit the patent’s scope.

Filing promptly can also help to reduce the risk of encountering such prior art. This is particularly important in fast-moving areas of technology, a category into which software inventions often fall.

In closing

Software is one of a number of constantly evolving, specialist fields within the patent profession. Many experienced patent attorneys don’t advise on software patents, in the same way that I don’t advise on complex pharmaceutical or biotechnology patents. Exposure to large numbers of software patent applications gives a practical insight that cannot be learnt from articles, books or courses.