Why Should September’s Opposition Filings Be on Your Watchlist?
A patent on your competitor watchlist may now face several challenges. Before your team changes a research priority, licensing position or product plan, it needs to know which patent is involved and what is being contested.
September’s EPO patent opposition report records 302 filings involving 236 distinct patents. Only 31 patents received more than one challenge. That is 13.1% of the opposed patents, making this smaller group a useful starting point for a closer review.
Boehringer Ingelheim’s EP4000608B1 received 10 challenges, the highest count reported for an individual patent. British American Tobacco led the opponent ranking with 12 filings. These figures identify where challenges were concentrated; the commercial implications depend on the claims and the evidence in each case.
What Did September EPO Opposition Filings Cover?
| Measure | September 2026 |
| Opposition filings | 302 |
| Distinct patents opposed | 236 |
| Patents receiving multiple challenges | 31 – 13.1% of opposed patents |
| Most challenged patent | EP4000608B1 – 10 filings |
| Owner receiving the most challenges | Boehringer Ingelheim – 10 |
| Most active named company group | British American Tobacco – 12 |
| Leading firm by recorded filings | Maiwald – 16 |
September’s filings show where challenges were concentrated, which companies were active and which patents attracted multiple opponents. For IP and R&D teams, these are starting points for identifying cases relevant to their portfolios and technologies.
Reading the figures: opposition filings and distinct patents are different measures because one patent can receive several oppositions. Company names follow the report’s group labels. Product descriptions identify reported areas of relevance, not a determination that a commercial product falls within the claims. Monthly figures: GreyB September 2026 opposition report.
Which Patent Owners Received The Most EPO Opposition In September 2026?
Boehringer Ingelheim received 10 challenges against one patent. Johnson & Johnson received nine across two patents, while Sanofi and Roche each received seven. The same filing count can therefore represent quite different workloads: several challenges to one patent, or challenges spread across several patents.
Seven of these nine owners are pharmaceutical companies. However, the ranking does not measure the likelihood of losing a patent. It also does not account for the size of each owner’s portfolio or the number of patents eligible for opposition.
Why Does The Number Of Distinct Patents Matter?
Imperial Brands received six challenges across four patents; Philip Morris International received five across four. By comparison, Boehringer Ingelheim’s 10 challenges concern a single patent. An IP team would approach these differently: the first calls for review across several files, while the second calls for a detailed comparison of objections and evidence directed at one patent.
For R&D teams, the next filter is technical relevance. A lower-ranked owner may matter more if the challenged claims concern a feature your team is developing. Use the ranking to locate cases, then use the claims to assess relevance.
Who Filed EPO Oppositions, And Whose Patents Did They Challenge In September 2026?
British American Tobacco filed 12 oppositions involving tobacco and vaping patents. Henkel followed with nine across adhesives, hair dyes and cleaning. Nestlé’s five filings involved five named company groups. The opponent-owner relationships make these figures more useful than a standalone activity ranking.
| Opponent | Filings | Owners named in the report |
| British American Tobacco | 12 | Philip Morris, Imperial Brands, Japan Tobacco, Kt&G |
| Henkel | 9 | Arkema, Sika, Kao, Beiersdorf, Reckitt And More |
| Nestlé | 5 | Colgate-Palmolive, Jde Peet’S, Frieslandcampina, Mondelēz, Bayer |
| Carl Zeiss | 4 | Leica Microsystems, Nikon |
| Phoenix Contact | 4 | Harting |
| HARTING | 4 | Phoenix Contact |
| Japan Tobacco | 4 | Philip Morris, Bat, Imperial Brands, Juul |
Phoenix Contact and HARTING each filed four challenges against the other’s patents. This reciprocal activity gives connector teams a specific pair of portfolios to examine. It does not, on its own, show a coordinated campaign or a wider legal dispute.
Which Law Firms Handled The Most EPO Opposition In September 2026?
| Law firm | Filings | Examples of clients listed |
| Maiwald | 16 | Lumara Bio, Egis, Gedeon Richter, Sasol |
| D Young & Co | 14 | BAT, Teva, Nestlé, Fresenius |
| Elkington and Fife | 10 | P&G, Nestlé, Sandoz, Polpharma |
| Marks & Clerk | 5 | Meril, Nestlé |
| Reddie & Grose | 5 | Sandoz, Synthon, Philip Morris |
These counts describe representation activity in the September report. They do not measure outcomes, legal quality or future success. For a team reviewing a particular case, the relevant detail is which representative acts for which party in that file.
Which Individual Patents Attracted The Most EPO Challenges In September 2026?
The report identifies 12 patents with at least three challenges, including nine medicine-related patents. The eight entries below show why patent-level review matters: an owner’s total may be driven largely by a single file.
| Patent | Owner | Reported product or technology | Filings |
| EP4000608B1 | Boehringer Ingelheim | Diabetes medicine | 10 |
| EP3519049B1 | Johnson & Johnson | Psoriasis medicine | 8 |
| EP4458350B1 | Sanofi | mRNA vaccine technology | 7 |
| EP4349406B1 | Pfizer | Heart medicine ingredient | 6 |
| EP4025192B1 | Novo Nordisk | Diabetes tablet | 5 |
| EP4403579B1 | Takeda | Bowel disease medicine | 4 |
| EP3060065B1 | Arla Foods | Milk protein ingredient | 4 |
| EP4183282B1 | Imperial Brands | E-cigarette | 3 |
Boehringer Ingelheim’s patent accounts for all 10 challenges attributed to the group. Johnson & Johnson’s EP3519049B1 accounts for eight of its nine. These are clear priorities for readers already tracking those portfolios.
The next question is whether opponents rely on the same objections and evidence. Several opponents may raise overlapping arguments, or focus on different parts of the claims. The filing count alone cannot distinguish those situations.
Which Technologies Had More Opponents in September 2026 EPO Opposition?
Medicine and biotechnology patents averaged 2.7 opponents per challenged patent, compared with 1.0-1.2 in the other reported industries. For owners in this group, reviewing how objections overlap across opponents is particularly relevant.
Which Product Appeared Most In September 2026 EPO Opposition?
Antibody medicines led the product-group chart with 22 filings, followed by heated tobacco and e-cigarettes with 21, and diabetes medicines with 15. These broad groups provide a first filter for readers who monitor technologies rather than individual owners.
A product-group label is the beginning of the analysis. Readers still need to examine whether the challenged claim concerns a composition, a process, a device feature or a particular use. That distinction determines which R&D or business team should review the file.
What Evidence Could Support Your Response To An Opposition?
Facing an opposition to one of your patents? GreyB can support your patent counsel by analysing the opponent’s objections, examining the cited prior art and identifying technical distinctions that may support your response. Where changes to the claims are being considered, we can help assess technical features disclosed in the original application that may support alternative claim sets, known as auxiliary requests. These are considered if a higher-ranking request is not allowable. Any changes must follow European patent rules, stay within the original disclosure and not broaden the patent’s protection. The goal is to support your counsel’s assessment of options that retain commercially relevant protection.
