Opposition before the granting office: costs drivers
Opposition before the granting office is decided by internal procedure, not by price lists. The main cost drivers are the number of grounds raised, the volume of prior-art evidence, and whether oral proceedings are requested. A single-ground opposition with clean evidence resolves faster than a multi-ground file contested on procedure.
Cost drivers, one by one
The cost of an opposition rarely comes from the filing fee. It comes from how many separate questions the file forces the office to examine, and how many times the parties have to respond to each other before a decision can be reached.
- Number of grounds raised. Each additional ground — novelty, inventive step, added subject matter, insufficient disclosure — adds a line of argument the other side has to answer and the office has to weigh separately.
- Volume of prior-art evidence. A file built on two documents moves faster than a file built on twenty, because every document has to be read, compared and, where needed, translated.
- Number of parties. Where several opponents challenge the same right, the office usually joins the proceedings, and each party's submissions have to be served on all the others.
- Oral proceedings. A hearing adds preparation time on both sides and a further exchange of written observations before the date is fixed.
- Expert input. Where a ground turns on a technical point the office cannot resolve from the documents alone, an expert opinion extends the file and the timetable.
- Appeal risk. A decision likely to be appealed is usually drafted, and argued, more carefully than one neither side is expected to contest further.
These drivers combine. A single-ground opposition supported by two documents, filed by one opponent who does not ask for a hearing, is close to the simplest and cheapest version of the procedure. Everything else adds stages, and every added stage adds time before either side gets a decision it can rely on.
What happens once the file opens
Once a party lodges a notice of opposition, the granting office checks the file for admissibility before looking at substance. An admissible notice must name the contested right, state the grounds relied on, and attach supporting evidence within the window the office sets for that purpose. A notice missing any of these elements is usually rejected on formal grounds, without the merits being examined at all.
After admissibility is confirmed, the office invites the holder of the contested right to respond in writing. Both sides then exchange further submissions, often more than once, until the office considers the file ready for a decision or for oral proceedings. Nothing in this exchange is automatic: each round has to be requested, allowed or ordered, and each round adds time.
Stages and what drives their length
| Stage | What happens | What drives cost and time |
|---|---|---|
| Filing and admissibility check | Office verifies form, standing and grounds | Completeness of the notice; number of grounds pleaded |
| Written exchange | Holder responds; opponent may reply | Number of rounds the office allows or the parties request |
| Evidence and expert input | Prior art, expert opinions and translations are added to the file | Volume and language of the evidence; need for translation |
| Oral proceedings | Held if either party requests them or the office considers them necessary | Whether a hearing is requested; number of parties and grounds |
| Decision and appeal window | Office issues a written decision; either side may appeal within the fixed window | Whether the losing side appeals; scope of the appeal |
Documents needed to start
An opponent typically needs the following in place before the notice can be filed, and gathering them is itself a cost driver, since missing items delay the admissibility check:
- Identification of the contested right and the decision that granted it, so the office can locate the correct file.
- A statement of the grounds relied on, set out separately for each ground rather than combined into a single argument.
- Prior-art documents or other evidence supporting each ground, in a form the office can examine directly.
- Certified translations, where any of the evidence is not in the language used in the proceedings.
- Proof of representation, where a representative rather than the opponent itself signs the notice.
For evidence collected from digital sources, the same discipline applies as for any other record: who accessed it, when, and whether it was altered before it reached the file. The underlying logic is close to Custody and control review step by step in detail, even though the right at stake there is not a patent.
Who decides and on what basis
The decision is taken by a panel or division inside the granting office, not by a single examiner acting alone. The panel reviews the written file and, where a hearing was held, the record made during that hearing. Its decision is reasoned and issued in writing, and it can usually be challenged before a separate appeal body that sits inside the same office rather than in an ordinary court.
Entitlement disputes sometimes surface inside an opposition, particularly where the underlying invention was developed by more than one contributor. Where a freelancer contributed to the work without a signed assignment, the question of who actually owns the right can outweigh every other ground raised in the file. That situation is covered separately, because it changes the cost calculation before the opposition itself is even reached: When freelancers signed nothing explained.
The point of no return
Once the opposition period closes, no new opposition against the same grant can be filed by that party. Grounds not raised within the period are, as a rule, excluded from the file that follows, even where stronger evidence for them surfaces later.
What this page does not settle
This page sets out what drives the cost of an opposition; it does not quote the official fees, which the granting office publishes in its own schedule, and it does not estimate your total exposure, which depends on the grounds raised, the volume of evidence, and whether a hearing is held. It does not decide whether opposing is the right move in your case.
FAQ
What drives the cost of an opposition?
The number of grounds argued, the volume and translation of evidence, whether an oral hearing is held, and whether an entitlement question is raised alongside the main grounds. Each adds preparation rather than a fixed line item.
Which deadline is already running?
The opposition period itself. Once it closes, that party cannot file a fresh opposition against the same grant, and grounds not raised inside the period are, as a rule, excluded from what follows.
Who decides, and on what evidence?
The opposition body inside the granting office decides first, on the written record and any hearing held. Its reasoned decision can usually be challenged before a separate appeal body that sits inside the same office rather than in an ordinary court.
Verified
Checked against the granting office's published opposition guidance, current at the time of writing. Official fees are set by the office and are not reproduced here. The review date for this page is shown in its metadata.