---
title: "LEARN market-history catalog (defunct companies + events)"
method: GET
path: "/api/learn/market-history"
tags: ["Education"]
---

# LEARN market-history catalog (defunct companies + events)

`GET /api/learn/market-history`

## Request

- Base URL: `https://www.oxfordledge.com` (the document declares no server; this is the origin it was published from)
- URL: `https://www.oxfordledge.com/api/learn/market-history`
- Auth: none declared

Return the market-history catalog as `{companies: [...]}`.

Mirrors `static/data/defunct-companies.json` shape so
`static/js/defunct-companies.ts:89` can swap fetch URLs without
renderer changes.

Falls back to the JSON file when PG is empty.

## Response `200`

Successful Response

- LearnDataMarketHistoryResponse: `GET /api/learn/market-history` response. Top-level shape matches `static/data/defunct-companies.json` — `companies[]` is the load-bearing list. Each entry carries the full timeline payload (`timeline`, `key_figures`, `key_documents`, etc.) plus the v96 editorial additions (`magnitude`, `investment_lore_xref`, `is_year_anchor`, `event_date`) and the v266 `event_date_precision` when PG is the source.
  - `companies` LearnMarketHistoryCompany[], required
    - `id` string, nullable
    - `name` string, nullable
    - `defunct` integer, nullable: Year of failure / the event's year; the timeline's year when `event_date` is absent.
    - `event_date` string, nullable: ISO YYYY-MM-DD. Month precision = the 1st of the month, year precision = 1 January; read `event_date_precision` before displaying the day or month.
    - `event_date_precision` 'day' | 'month' | 'year', nullable: How much of `event_date` is documented: day | month | year. Present exactly when `event_date` is.

## Other responses

- `500`: Internal Server Error

---

[API](https://skmtc.dev/oxfordledge/apis/oxford-ledge-api.md) · [All operations](https://skmtc.dev/oxfordledge/apis/oxford-ledge-api/llms.txt) · [OpenAPI document](https://skmtc.dev/oxfordledge/apis/oxford-ledge-api/revisions/e832a1260f0b?raw)