Ever wondered how a company can challenge a rival’s patent without anyone ever finding out who really did it? Meet the company that makes it possible.
Patents are meant to protect ideas. But sometimes, a patent is granted that never should have been – and someone needs to challenge it. In Europe, any person or company can file an opposition against a patent within nine months of it being granted by the European Patent Office (EPO). Simple enough, right? Except there is one problem. The moment you file an opposition, your name goes on public record for the whole world to see, including your competitors.
This is exactly where a quiet, unusual company called Strawman Limited steps in. It does not make products. It does not sell anything to the public. Its entire business is built around one simple idea – helping companies oppose a patent without ever revealing who they really are.
What Exactly Does Strawman Limited Do?
Strawman Limited is a service company whose sole objective is to provide anonymity to any company or firm wishing to oppose a patent. In plain words, when a business wants to challenge a European patent but does not want its name attached to the case, Strawman Limited steps in and becomes the official, named opponent instead.
Since 2000, Strawman Limited has been quietly providing anonymous patent oppositions, giving it close to 25 years of experience in helping third parties challenge European patents while staying completely out of sight.
The process works smoothly because the real company never has to appear anywhere in the paperwork. Strawman’s name is used on a first-come, first-served basis, and the service is built so that it should never refuse the use of its name, as long as the proper legal steps are followed. A European Patent Attorney, or another representative authorised to act before the European Patent Office, is required to formally set this arrangement in motion.
Why Would Any Company Want to Stay Anonymous?
It might sound a little mysterious at first, but staying anonymous during a patent opposition is a smart, and completely legitimate, business strategy. Here is why companies choose this route:
• Hidden – Competitors never find out that you are interested in their technology.
• Influence – You can negotiate a patent licence directly and on friendly terms with the patent owner, while your opposition runs quietly in the background.
• Freedom – You can build stronger, bolder arguments that you might not be able to use if your own name were on the case.
• Competitiveness – Staying hidden can give you a real edge over rivals who don’t know what you are working on.
There is also a more relationship-driven side to this. Sometimes a company needs to challenge a patent belonging to a supplier, a customer, or even a business partner. Doing that openly could damage the relationship. By using Strawman Limited, a company can protect its interests without any of the awkwardness that would come from opposing a partner by name.
The Numbers Behind the Name
Strawman Limited does not talk about itself often, but the patents it has helped oppose tell their own story. Over the years, it has quietly gone up against some of the biggest names in pharmaceuticals, biotechnology, and research – without ever revealing who was really behind each challenge.
Who are the Top patent owners to whom Strawman Limited is opposing?
| Patent Owner | Oppositions Filed |
| Amgen | 13 |
| Novartis | 12 |
| Chugai Seiyaku Kabushiki Kaisha | 11 |
| Curevac | 7 |
| F. Hoffmann-La Roche | 6 |
| Nippon Steel | 6 |
| The Broad Institute | 6 |
| Novo Nordisk | 5 |
| University Of Pennsylvania | 5 |
| University Of Tokyo | 5 |
Notice something interesting here? Most of the names on this list are giants of the pharmaceutical and biotech world, alongside a few leading research institutions. This makes sense – patent oppositions at the EPO happen most often in the healthcare and life sciences sector, where a single patent can be worth an enormous amount of money.
What Do Strawman Limited EPO Patent Opposition Trends Reveal?
Patent opposition activity does not stay the same every year – it rises and falls depending on how many patents are granted, how competitive an industry becomes, and how often companies choose anonymous opposition filing to protect their interests. Here is a year-wise look at how many oppositions were filed with Strawman Limited as the named opponent.
| Filing Year | Opposition Count |
| 2015 | 24 |
| 2016 | 29 |
| 2017 | 35 |
| 2018 | 44 |
| 2019 | 40 |
| 2020 | 48 |
| 2021 | 36 |
| 2022 | 47 |
| 2023 | 32 |
| 2024 | 47 |
| 2025 | 58 |
| 2026 | 31 |
This steady flow of opposition filings, year after year, shows that anonymous patent opposition is not a one-time trick used by a handful of companies. It is an ongoing, dependable part of how businesses across Europe manage risk and protect their competitive position. The jump to 58 oppositions in 2025 stands out as the busiest year yet for Strawman Limited, suggesting that demand for anonymous opposition filing keeps growing as more companies discover the benefits of a trusted patent opposition service.
Which Technology Sectors Face the Most EPO Opposition from Strawman Limited?
| Technology | Oppositions Files |
| Healthcare | 333 |
| Industrial and Manufacturing Technology | 76 |
| Energy and Environmental Technology | 32 |
| Food and Agriculture | 26 |
| Materials Science | 2 |
| Automotive | 1 |
Healthcare receives the highest number of patent oppositions filed through Strawman Limited by a wide margin, totalling 333 cases. This strong focus aligns with broader European Patent Office (EPO) trends, where medical and pharmaceutical sector exclusivity directly affects market entry, pricing, and commercial opportunities.
What is the Outcome Status of Oppositions Filed by Strawman Limited?
| Filing Year | Opposition Count |
| Revoked | 218 |
| Pending | 103 |
| Maintained as Amended | 101 |
| Opposition Rejected | 39 |
| Withdrawn | 10 |
Notice something interesting here? Nearly half of all oppositions filed (218 out of 471, or 46%) result in the patent being Revoked – meaning Strawman Limited’s oppositions are succeeding at a very high rate. Add in the 101 cases Maintained as Amended, and roughly 68% of resolved oppositions end in the original patent being changed in some way, rather than surviving intact. Only 39 cases (8%) see the Opposition Rejected, where the patent holder successfully defends their claim as-is. With 103 cases still Pending, there’s a substantial pipeline of outcomes yet to play out – and if the current pattern holds, most of these are likely to end in revocation or amendment too.
Which are the Top law firms handling Opposition cases for Strawman Limited?
| Law Firm | Oppositions Handled |
| Mewburn Ellis | 57 |
| Vossius & Partner Patentanwälte | 53 |
| Hoffmann Eitle | 45 |
| D Young & Co | 36 |
| Potter Clarkson | 27 |
| Cabinet Plasseraud | 19 |
| CMS Cameron McKenna | 14 |
| Greaves Brewster | 13 |
| Carpmaels & Ransford | 12 |
| Brand Murray Fuller | 8 |
Mewburn Ellis tops this list by quite a distance, having handled 57 oppositions where Strawman Limited was the named party. What makes this even more interesting is that Mewburn Ellis actually runs its own separate anonymity vehicle too. Yet, its heavy use of Strawman Limited shows just how deeply trusted and widely relied upon this service has become across the European patent industry, not just among smaller firms, but among the biggest names in the business.
Conclusion
Strawman Limited proves that not every powerful player in the patent world needs to be visible to be effective. By quietly stepping into the spotlight on behalf of others, it allows companies to fight for their interests, protect their business relationships, and stay a step ahead of their competition – all without ever revealing their hand. In a world where information is power, sometimes the smartest move a company can make is choosing not to be seen at all.
For a broader look at how this fits into the wider picture, see our analysis of EPO patent opposition trends from 2021 to 2026, which covers the industries, companies, and law firms driving opposition activity across Europe
This kind of thing happens more often than you’d think. Companies challenge patents without putting their name on it – to protect a business relationship, negotiate quietly, or just stay under the radar. If you want to find out who’s really behind an anonymous opposition, or keep an eye on oppositions filed against your own patents, GreyB can help.
Knowing who filed the opposition is just the start. The real question is what it means for you – is a competitor testing your patent, or is your own portfolio at risk of being challenged next?
GreyB can help you trace the real party behind an anonymous opposition, flag which of your patents are most likely to be challenged, and track opposition trends in your industry so you’re never caught off guard.
