When the other side files revocation first: what it costs to be wrong
A revocation action filed against your patent is not a formality. It opens a countdown, forces early disclosure of your defence, and can suspend a related infringement claim until validity is settled. Being wrong about the forum, the deadline, or the required evidence costs the case itself, not merely time.
The basis for the action
For a European patent with unitary effect, revocation is heard by the Unified Patent Court under the Agreement on a Unified Patent Court. Substantive protection for such patents rests on Regulation (EU) No 1257/2012. Translation duties for pleadings and evidence follow Council Regulation (EU) No 1260/2012.
What changes once revocation is filed
Filing starts the clock on your response. A late or incomplete answer can be treated as accepting the grounds raised, even where the patent would otherwise survive. Any pending infringement claim on the same patent is affected: most forums will not decide infringement while validity is contested.
The dispute sometimes traces back to ownership rather than prior art, as in When a former employee launches a similar product and disputes who filed first. Check the assignment chain before assuming the challenge rests on technical grounds alone.
What to do, in order
- Confirm the forum named in the writ and the deadline it states; do not assume a default period applies.
- Assemble the granted patent, the full prosecution history, and any licence or assignment records tied to the claim.
- Instruct counsel to prepare the defence against the stated deadline, not against an informal expectation from the other side.
- Check whether an infringement claim is already pending, and confirm whether the revocation stands alone or as a counterclaim.
- Preserve internal correspondence around the invention's origin; ownership challenges are decided on records, not recollection.
How firm-side turnaround on enquiries like this is measured is shown openly; see Delivery statistics, published automatically and the deadline it reports against.
Who decides, and on what
| Stage | Forum | Basis |
|---|---|---|
| Revocation action, unitary patent | Central division of the Unified Patent Court | Agreement on a Unified Patent Court |
| Translation of pleadings and evidence | Registry of the division seized | Council Regulation (EU) No 1260/2012 |
| Substantive validity | Panel hearing the action | Regulation (EU) No 1257/2012 |
The panel decides on the granted patent, the prosecution file, and the evidence both sides submit within the deadlines the court sets and states in the writ. Those deadlines are procedural, not fixed by the acts above; the acts set the forum and its rules, not the calendar for a given case.
If your situation differs
If the patent is a national grant rather than a unitary one, the forum is your national office or court, not the Unified Patent Court described here.
If the challenge invokes a licensing chain rather than technical prior art, verify who currently holds the enforceable right before assuming the licensor's authority is settled; see When a token claims to carry a licence step by step through that check.
If revocation arrives together with an infringement counterclaim, treat the two as one file. Evidence submitted for one side of the dispute binds the other.
What this page does not cover
This page does not set out how long a defence takes to prepare, what it costs, or how a specific claim will be decided. It does not describe national revocation procedures outside the unitary patent system in detail, and it does not cover appeal routes once a first decision is issued.
Sources and limit
Checked against the sources listed below; last reviewed in 2025. Primary sources: Agreement on a Unified Patent Court; Regulation (EU) No 1257/2012; Council Regulation (EU) No 1260/2012.
The same discipline of acting before a deadline runs, applied to a different risk, is set out in Counterparty report before extending credit explained.
Related reading
For the related failure pattern after grant, see When prior art surfaces after grant in practice.
Frequently asked questions
What is the first step when the other side files revocation first?
Confirm the forum and the deadline stated in the writ before drafting any response. Acting on an assumed deadline is the most common early mistake.
Which deadline is already running?
The deadline set by the forum seized starts on service of the action, not on the date you notice it or decide to respond.
Who decides, and on what evidence?
The panel hearing the revocation decides, on the granted patent, the prosecution file, and whatever evidence both sides file within the set deadlines.
A partner responds within minutes during business hours. An estimate for preparing the defence follows within one business day.