Evidence gathering in two countries: documents to prepare
When a patent dispute spans two countries, evidence has to satisfy two sets of rules at once. A statement, an invoice or a lab report accepted at home may be rejected abroad without the right form, translation or notarisation. This page lists what to prepare, who checks it, and where the process can stall.
What changes once two countries are involved
A single-country dispute treats evidence as one file. Two countries treat it as two files that have to match. The first court expects its own certification chain; the second checks the same document against its own admissibility test. A missing stamp, an uncertified translation or a gap in the custody log gives either side a reason to challenge the evidence rather than argue its content.
Digital records add a further layer. If the underlying invention touches distributed ledgers, an on-chain entry with no matching off-chain record raises a separate recognition question — see When a transfer on-chain is not recorded off-chain and. That question is settled before the ledger entry can be used as evidence at all.
Documents to prepare
The list below covers the documents that come up in most two-country files. Not every dispute needs every row; a file with no witness abroad skips the notarised statement, for example.
| Stage | Document | Prepared by |
|---|---|---|
| Before the request is filed | Inventory of exhibits, one reference number per item | Client and counsel together |
| Before the request is filed | Certified translation into the receiving court's working language | Sworn translator instructed by counsel |
| Witness is abroad | Notarised witness statement, signed before a local notary | Witness, at a local notary's office |
| Document crosses the border | Legalisation or apostille certificate, where the receiving country requires one | Notary or issuing authority |
| Request is sent | Formal request for evidence, addressed to the receiving court | Counsel |
| Throughout the file | Custody log recording every hand-off of the original document | Client's document controller |
Who decides and what to expect
The receiving court decides whether the request is complete and whether the evidence, once gathered, is admissible. It does not decide the underlying patent dispute — that stays with the court that issued the request. Between filing and the first substantive response, expect the process to run in weeks rather than days. A second round, if a document is rejected on form, adds a comparable delay.
Three situations, three routes
- If every document already carries a certified translation, the request moves straight to the receiving court's admissibility check.
- If a witness is abroad and cannot travel, a notarised statement taken locally replaces in-person testimony, subject to the receiving court accepting the format.
- If the other side controls the evidence and will not hand it over voluntarily, the request itself becomes the tool that compels disclosure.
Each route changes the timeline, not the list of documents. The inventory, the translation and the custody log are prepared in every case, before either side knows which route the file will take.
What this page does not decide
This page does not establish who holds a claim against a counterparty, and it does not check a counterparty's standing before a dispute starts. That check sits in a separate file — see Counterparty in Estonia in detail for what a due-diligence report on an Estonian party can and cannot establish before evidence gathering begins.
Verified
This page describes procedure only. It does not cite a specific statute, because the file that would let us verify a matching national provision on both sides is not yet complete for this route. Copies of documents gathered under this procedure are kept under our own retention rules — see Retention: the report, the extracts and our copy. Reviewed by the author on 10 February 2025.
Related
For the cost side of running a dispute across two countries, see Costs and security for costs step by step.
Next step
If the evidence file rests on a database built by a supplier rather than in-house, ownership of that file follows its own separate check — see When the database was built by a supplier step. Where a two-country evidence file is already underway, send it to us before it goes to either court.
Frequently asked questions
How long does evidence gathering in two countries take in practice?
Plan for weeks rather than days between the request and the first substantive response. A document rejected on form for a missing translation or certificate adds a further round of comparable length.
Which documents are needed to start?
An inventory of exhibits with a single reference number per item, a certified translation into the receiving court's working language, and a custody log covering every hand-off. Notarised statements and legalisation certificates join the file only where a witness or document crosses a border.
What happens if the other side does not respond?
Silence does not stop the file. The requesting party can ask the court to compel a response or draw its own conclusions from the refusal, depending on how the request was framed. The custody log and the inventory matter more, not less, once cooperation stops.