> ## Documentation Index
> Fetch the complete documentation index at: https://docs.signa.so/llms.txt
> Use this file to discover all available pages before exploring further.
# Compute Oppositions
> Compute trademark opposition windows from publication dates
## Overview
Compute the opposition window for a published mark — when it opens, when it closes, and how much time is left — from a publication date, without storing anything.
Opposition windows are short, unforgiving, and specific to each office. When a conflicting mark publishes, the oppose-by date is what separates a cheap, procedural opposition now from a costly cancellation later. Send a publication date and Signa returns the window, its current status, any routine extensions, and the office rule behind it.
Pair it with [List Opposition Rules](/api-reference/reference/opposition-rules) to inspect the office rules, trigger events, time zones, extensions, and citations behind each computation.
Reference → Oppositions is the forward-looking WINDOW/timing computed from a publication date. Records → Proceedings (per-mark) is actual filed opposition CASES. They are distinct.
## Request Body
Publications to compute, max 1,000 items. Results are returned in the same order, with one `opposition_window` per input item.
Trademark office code, e.g. `uspto`, `euipo`, or `cipo`. Values are normalized to lowercase.
Filing route. One of `national`, `regional`, or `madrid`. Defaults to `national`. The response reports the office rule discriminator as `domestic` or `madrid_designation`.
Publication calendar date as `YYYY-MM-DD`. Omit when the publication date is unknown; the response status will be `unknown`.
Office-local calendar date to compute relative to, as `YYYY-MM-DD`. Defaults to today.
## Response
A standard list response with `data: OppositionWindowComputation[]`. Pagination is not used; `data[i]` corresponds to `items[i]`.
Always `list`.
Always `opposition_window`.
`true` when Signa has an opposition rule for the office and route.
`unsupported_office`, `window_not_computable`, or `null`.
Jurisdiction for the office rule, e.g. `EU`.
Office code used for the computation, e.g. `euipo`.
Rule discriminator: `domestic` or `madrid_designation`.
Publication date used as the trigger.
First day the opposition window is open.
Last day to oppose, after office-calendar rollover.
One of `not_started`, `open`, `closed`, or `unknown`.
Days until `window_opens` when the status is `not_started`.
Days remaining in the window when known.
IANA office time zone for display.
`application_publication`, `registration_publication`, or `international_designation_publication`.
Date the office rule was last verified.
Extension length in days.
Extension length in months.
Whether the extension is granted automatically on timely request.
Human-readable note for UI surfacing.
Statutory or office citation.
Authoritative URL for the citation.
Always `false`.
Always `{ "cursor": null }`.
Unique request identifier for support and debugging.
Unsupported offices or unsupported office-route combinations return `supported: false` with nullable window fields. A far-future or out-of-calendar-range item that cannot be rolled forward returns `unsupported_reason: "window_not_computable"` for that item only.
```json theme={null}
{
"object": "list",
"data": [
{
"object": "opposition_window",
"supported": true,
"unsupported_reason": null,
"jurisdiction_code": "EU",
"office_code": "euipo",
"filing_route": "domestic",
"publication_date": "2026-05-01",
"window_opens": "2026-05-02",
"window_closes": "2026-08-03",
"status": "open",
"days_until_open": null,
"days_remaining": 29,
"office_time_zone": "Europe/Madrid",
"trigger_event": "application_publication",
"rule_version": "2026-05-06",
"common_extension": null,
"source": {
"citation": "Article 46(1) EUTMR (Regulation (EU) 2017/1001)",
"url": "https://eur-lex.europa.eu/eli/reg/2017/1001/oj/eng"
}
}
],
"has_more": false,
"pagination": { "cursor": null },
"request_id": "req_bT9kM3nP"
}
```
## Code Examples
```bash cURL theme={null}
curl "https://api.signa.so/v1/oppositions/compute" \
-H "Authorization: Bearer sig_xxxxxxxxxxxx" \
-H "Content-Type: application/json" \
-d '{
"items": [
{
"office": "euipo",
"publication_date": "2026-05-01"
}
],
"as_of_date": "2026-07-05"
}'
```
```typescript TypeScript SDK theme={null}
import { Signa } from "@signa-so/sdk";
const signa = new Signa({ api_key: "sig_xxxxxxxxxxxx" });
const windows = await signa.oppositions.compute({
items: [{ office: 'euipo', publication_date: '2026-05-01' }]
});
for (const window of windows.data) {
console.log(window.office_code, window.status, window.window_closes);
}
```
```python Python theme={null}
import requests
resp = requests.post(
"https://api.signa.so/v1/oppositions/compute",
headers={
"Authorization": "Bearer sig_xxxxxxxxxxxx",
"Content-Type": "application/json",
},
json={
"items": [{"office": "euipo", "publication_date": "2026-05-01"}],
"as_of_date": "2026-07-05",
},
)
for window in resp.json()["data"]:
print(window["office_code"], window["status"], window["window_closes"])
```
## Errors
| Status | Type | Description |
| ------ | ------------------ | ----------------------------------------------------------------------------------------------- |
| 400 | `validation_error` | Malformed body, missing `items`, invalid date format, invalid enum value, or unknown body field |
| 401 | `unauthorized` | Missing or invalid API key |
| 403 | `forbidden` | API key missing the `trademarks:read` scope |
| 422 | `batch_too_large` | More than 1,000 items. The error carries `item_count` and `item_count_limit` |
| 429 | `rate_limited` | Too many requests |
## Related Endpoints
* [List Opposition Rules](/api-reference/reference/opposition-rules) -- inspect the office rule corpus and statutory citations
* [List Proceedings](/api-reference/proceedings/list-proceedings) -- actual filed opposition, cancellation, and appeal cases
* [Trademark Proceedings](/api-reference/trademarks/trademark-proceedings) -- proceedings scoped to one mark