EPOObservations & Oppositions builder
Notice of opposition
Art. 99 EPC
The one procedure that lets anyone have a granted European patent revoked centrally, in every designated state, with one filing and one fee. It must be filed within nine months of the mention of grant and makes you a party.
At a glance
9 months from grant mention
EUR 880 opposition fee, code 010 (checked 22 Sep 2026)
- Who can file
- Any person, natural or legal, without showing an interest. Not the proprietor (G 9/93).
- Deadline
- Nine months from publication of the mention of grant. No further processing, no re-establishment.
- Official fee
- EUR 880, fee code 010, paid within the same nine months. No reduction.
- Language
- English, French or German. An Art. 14(4) EPC filer may use its own language and file a translation in time.
- Anonymous
- No. Identity must be established within the nine months; a named straw man for an undisclosed client is allowed (G 3/97).
- Representation
- Compulsory from filing only if the opponent has no residence or principal place of business in a contracting state.
- How it is filed
- Online Filing 2.0, procedure EP 2300, or by post or hand. Contingency Upload Service in an emergency. Not fax, not MyEPO.
- Party status
- Yes. The opponent is heard, may request oral proceedings and may appeal.
What it is
Notice of opposition, in brief
Any person except the proprietor can oppose, without showing an interest, within nine months of the mention of grant. The opponent becomes a party, with the right to be heard, to oral proceedings and to appeal. The patent may be revoked, maintained, or maintained as amended, in all designated states.
The extent, the grounds and the facts and evidence must all be filed inside the nine months: Rule 77(1) EPC defects cannot be cured afterwards. Only Art. 100 EPC grounds count; clarity, unity and prior national rights are not grounds.
Grounds it can carry
- Lack of noveltyArt. 100(a) with Arts. 52(1) and 54 EPC
- Lack of inventive stepArt. 100(a) with Arts. 52(1) and 56 EPC
- Not patentable on other groundsArt. 100(a) with Art. 52(2), 52(3), 53 or 57 EPC
- Insufficiency of disclosureArt. 100(b) EPC
- Subject-matter beyond the application as filedArt. 100(c) EPC
Use it when
- The mention of grant is under nine months old and you want the patent revoked or cut down everywhere at once.
- You want control of the case: to be heard, to attend oral proceedings, to answer amendments and to appeal.
- The patent has lapsed or been surrendered everywhere, but past damages still matter (Rule 75 EPC).
Choose another route when
- The mention of grant is not yet published: an early notice is treated as observations and the fee refunded. Third-party observations
- The nine months have passed, an opposition or appeal is pending, and you have been sued on the patent. Intervention of the assumed infringer
- The nine months have passed and nothing is pending at the EPO. Revocation action
How IPtorch builds it
From search to filing, minus the signature.
The invalidity search runs on into this filing when it ends, with no second click. Three model families take turns, so a draft is never checked by the model that wrote it.
- 1SearchClaims split into limitations, thousands of candidates screened, at least 50 references read in full.Gemini models read and check
- 2Claim mapA verbatim quotation and its location behind every limitation.Every cell checkable
- 3DraftWrites the papers in the office's format and language.Claude Opus 5.5 (Anthropic)
- 4ReviewChecks each citation against its document and builds the forms.Sol 6 (OpenAI)
- 5AdjudicateHigh strength: a third family rules on every objection.Gemini 3.1 Pro (Google)
- 6FolderUnsigned PDFs, ready for a professional to review, sign and file.Nothing is filed
What the builder does for this filing
- It refuses the job before any spend if the opponent's name and address are missing, because an opposition cannot be anonymous.
- It starts from an invalidity search with at least 50 references read in full, re-qualifies each reference under the EPC's own prior-art rule, and maps every feature of each attacked independent claim to a pinpointed passage.
- It argues inventive step from the closest prior art through the distinguishing features, the effect and objective problem, to the motivation to combine, so no link in the chain is left implicit (T 1194/07).
- It states the extent and each Art. 100 ground before any argument, keeps clarity, unity and prior national rights out, and requests oral proceedings as an auxiliary request.
In the folder
- Form 2300 field valuesFor Online Filing 2.0, procedure EP 2300
- Facts, evidence and argumentsAnnex 1 to Form 2300: patent, skilled person, construction, grounds, dependent claims
- List of evidenceD1 upward, Form 2300 section IX, with dates of public availability
- Front sheetFree-standing notice route only, in place of Form 2300
- Copies of every cited documentSeparate PDFs numbered D1 upward
- Labelled machine translationsBeside the original, for prior art not in English, French or German
Builder strength
You choose how hard it is checked.
You pay for the tokens the sessions use, at the models' list prices plus a 30% fee, not for the time allowed. How pricing works
Low
- Opus 5.5 drafts the submission
- Sol 6 builds and checks the final forms
Medium
- Opus 5.5 drafts the submission
- Sol 6 reviews and rebuilds the content
- Opus 5.5 builds the filing folder
- Sol 6 checks the form
High
- Opus 5.5 drafts the submission
- Sol 6 runs a deep prior-art search
- Opus 5.5 rebuilds the submission against the evidence
- Sol 6 attacks it as an adversarial examiner
- Gemini 3.1 Pro adjudicates the objections
- Opus 5.5 applies the fixes and builds the filing folder
- Scripted checks of the filing folder
- Sol 6 audits the whole folder
- Convergence gate
If the gate fails, one repair round: opus 5.5 repairs what the gate found, sol 6 audits the repair, convergence gate, again.
What stays with you
You review, sign and file.
- Confirm the opponent's identity, and that it is not the proprietor or acting for it.
- Sign with a text-string or facsimile signature in Online Filing 2.0.
- Pay EUR 880 in time: debit order in the XML fee section, card or transfer.
- File through Online Filing 2.0, procedure EP 2300, and keep the electronic receipt.
Where these go wrong
What the builder guards against.
- A last-day notice that only hints at attacks to come: at least one ground must be fully substantiated inside the nine months (T 204/91).
- Fee short or late: the opposition is deemed not filed. A debit order written only into the PDF does not count.
Start with the evidence.
Upload the patent or enter its number. The invalidity search charts every claim, and the builder takes it from there.
Start an invalidity searchFacts checked against the office's rules on 22 September 2026. IPtorch is not a law firm and this page is not legal advice. The builder's output is unsigned work product for a registered professional to review, sign and file; nothing is filed and no fee is paid for you. Confirm current requirements, fees and deadlines with the receiving office.