---
title: "Api Ownership Timeseries"
method: GET
path: "/api/institutional-holders/timeseries"
---

# Api Ownership Timeseries

`GET /api/institutional-holders/timeseries`

## 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/institutional-holders/timeseries`
- Auth: none declared

Institutional ownership of a ticker ACROSS QUARTERS (X5, 13F time-series).

Reads the hot S3 summary layer (pg_get_ticker_ownership_timeseries) — one row
per quarter with the 13F reporting-holder count, total shares/value, and the
largest holders that quarter. Powers the quarter-over-quarter ownership panel.

Data source: SEC EDGAR 13F-HR filings (quarterly; ~45-day filing lag). The
error envelope returns `series: []` so the frontend iteration is NPE-safe.

## Query parameters

- `ticker` string, required

## Response `200`

Successful Response

- TickerOwnershipTimeseriesResponse: `GET /api/institutional-holders/timeseries` — institutional ownership of a ticker across quarters (X5, 13F warehouse; FORM13F_WAREHOUSE.md). `series` is iterated in the frontend without a null-check; declared REQUIRED so the error envelope MUST include it as [] (shape-drift defect class, same as OwnershipChangesResponse).
  - `ticker` string, required: Echoed ticker (uppercased).
  - `series` object[], required: Per-quarter ownership rows (oldest-to-newest): {quarter, n_holders, total_shares, total_value, top_holders[]}. The newest row may carry partial=true when the global ingest for that quarter is still mid-arrival (EXT-AUDIT #61).
  - `coverage_began` string, nullable: First broad-coverage quarter; present only when curated-era rows (global filer count <25% of peak) were trimmed (EXT-AUDIT #61).
  - `trimmed_quarters` integer, nullable: Curated-era rows trimmed (present with coverage_began).
  - `error` string, nullable

## Other responses

- `422`: Validation 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)