EPOObservations & Oppositions builder

Third-party observations

Art. 115 EPC

A free, written, reasoned submission telling the EPO why a published application should not be granted, or a patent not maintained. The division must consider it. You stay outside the proceedings: no party status, no appeal.

Start an invalidity search How IPtorch builds it
EPO Published application Claim 1 1a 1b 1c D1 cited document [0042] Observations Art. 115 EPC, D1 [0042]
Read, quote, tie to the claim, file the paper.

At a glance

After publication, while pending

No official fee (checked 22 Sep 2026)

Who can file
Any third party, natural or legal, with or without a representative. Not the applicant, the proprietor or a party to the proceedings.
Deadline
None. Any time after publication while proceedings are pending. In opposition or appeal, material filed after the nine-month period counts as late.
Official fee
None (OJ EPO 2025, A71 point 1).
Language
English, French or German. Evidence in any language, subject to a translation request (Rule 3(3) EPC).
Anonymous
Allowed at first instance, but you lose the acknowledgement, the invitation to correct and the three-month target. Boards routinely disregard them (T 146/07).
How it is filed
EPO online form at tpo.apps.epo.org, typed into the browser template or as an uploaded document. No account needed. Fax abolished.
Effect
The division must consider them and state the outcome in its next action. Public at once; copied to the applicant or proprietor.
Party status
None. No right to be heard, to oral proceedings, to a reply or to appeal.

What it is

Third-party observations, in brief

Any third party can file observations on a published European application or patent while proceedings are pending at the EPO. There is no fee and no deadline. The office sends them to the applicant or proprietor, and the division states the outcome in its next action. Named, substantiated observations in examination set a three-month target for that action.

The observer never becomes a party. There is no right to be heard, to a reply or to appeal, and nothing is considered once proceedings close. Observations go on the public file at once and cannot be kept confidential.

Grounds it can carry

  • Lack of noveltyArt. 54 EPC
  • Lack of inventive stepArt. 56 EPC
  • Unallowable amendmentsArts. 76(1), 123(2) and 123(3) EPC
  • Insufficiency of disclosureArt. 83 EPC
  • Lack of clarityArt. 84 EPC; in opposition or appeal, against amendments only
  • Excluded subject-matter or no industrial applicationArts. 52(2), 52(3), 53 and 57 EPC

Use it when

  • The application is published and in examination: the examining division has the widest remit and the three-month target applies.
  • The patent is in opposition and you hold art the opponent lacks, without becoming a party or paying a fee.
  • A proprietor's limitation or revocation request under Art. 105a EPC is pending; Arts. 84 and 123(2) EPC may be raised.

Choose another route when

  • You need party status, a hearing or an appeal, and the nine-month opposition period is still open. Notice of opposition
  • You have been sued on the patent and an opposition or appeal is pending. Intervention of the assumed infringer
  • The application is not yet published, or is a PCT application still in the international phase (file with the IB through ePCT).

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.

  1. 1SearchClaims split into limitations, thousands of candidates screened, at least 50 references read in full.Gemini models read and check
  2. 2Claim mapA verbatim quotation and its location behind every limitation.Every cell checkable
  3. 3DraftWrites the papers in the office's format and language.Claude Opus 5.5 (Anthropic)
  4. 4ReviewChecks each citation against its document and builds the forms.Sol 6 (OpenAI)
  5. 5AdjudicateHigh strength: a third family rules on every objection.Gemini 3.1 Pro (Google)
  6. 6FolderUnsigned PDFs, ready for a professional to review, sign and file.Nothing is filed

What the builder does for this filing

  • It starts from an invalidity search with at least 50 references read in full, and re-qualifies each reference under the EPC's own prior-art rule, with its date of public availability.
  • It writes one section per objection: novelty as a feature-by-feature map, inventive step in the online form's four parts with the closest prior art first.
  • Every citation is pinpointed by page, column and line, or by paragraph or figure, and each document is marked as new to the file or already on it.
  • It checks that the application is published, proceedings are pending and no grant decision has been handed over, and it keeps out procedural complaints and any claim to party rights.

In the folder

  • Observations under Art. 115 and Rule 114 EPCOne section per objection, naming the article, claim and passages
  • Online form entries for tpo.apps.epo.orgField values for the EPO browser template
  • Covering letterLetter route only, for a hand signature
  • Copies of every cited documentNumbered D1 upward, ready to upload with the form
  • Labelled machine translationsBeside the original, for documents 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

40 minutesabout 10 million tokens (roughly $10 to $30)

  1. Opus 5.5 drafts the submission
  2. Sol 6 builds and checks the final forms

Medium

2 hoursabout 20 million tokens (roughly $20 to $60)

  1. Opus 5.5 drafts the submission
  2. Sol 6 reviews and rebuilds the content
  3. Opus 5.5 builds the filing folder
  4. Sol 6 checks the form

High

5 to 6 hoursabout 60 million tokens (roughly $50 to $200)

  1. Opus 5.5 drafts the submission
  2. Sol 6 runs a deep prior-art search
  3. Opus 5.5 rebuilds the submission against the evidence
  4. Sol 6 attacks it as an adversarial examiner
  5. Gemini 3.1 Pro adjudicates the objections
  6. Opus 5.5 applies the fixes and builds the filing folder
  7. Scripted checks of the filing folder
  8. Sol 6 audits the whole folder
  9. 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.

  • Decide knowingly whether to file named, anonymously or through a representative.
  • Approve the final text.
  • File through the EPO online form at tpo.apps.epo.org and keep the receipt PDFs.
  • Letter route only: sign by hand, with the name in block capitals.

Where these go wrong

What the builder guards against.

  • Filing anonymously, then relying on the observations at appeal: boards routinely disregard anonymous observations (T 146/07).
  • A pile of documents with no reasoning: name the claim and the passage so a skilled reader can follow without research (T 189/92).

More filings in Europe

EPO, UPC and national courts

All 17 filings

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 search

Facts 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.