---
title: "Holders-of-CUSIP Δ over the last N retained quarters"
method: GET
path: "/api/v1/sec/13f/holders-of/{cusip}/changes"
tags: ["Hedge Fund Intelligence"]
---

# Holders-of-CUSIP Δ over the last N retained quarters

`GET /api/v1/sec/13f/holders-of/{cusip}/changes`

Holder-level delta for one CUSIP across the N most-recent retained quarters (default 2, max 4 by memory bound). Computes added / removed / changed holders comparing earliest vs latest stem in the window. Intermediate stems contribute to `consensus_trend` (per-stem holder_count + total value + total shares) for sparkline rendering. `quarters_used` echoes the effective N. Out-of-range (1 or 5+) is REJECTED with 400 - no silent clamping. Internally uses streaming diff to bound memory ~one shard regardless of N.

## Path parameters

- `cusip` string, required — 9-character canonical CUSIP.

## Query parameters

- `quarters` integer — Number of retained quarters to compare (range 2-4 inclusive). Out-of-range = 400; no silent clamping.

## Response `200`

Multi-quarter delta-holders + consensus trend for one CUSIP.

- EnvelopeSec13fCusipChanges
  - `data` Sec13fCusipChanges, required — Delta-holders for one CUSIP over N quarters (2-4 per memory bound).
    - `cusip` string, required
    - `issuer` string, required
    - `quarters_used` integer, required — Effective number of quarters in the comparison (echoes request).
    - `quarters` Sec13fQuarter[], required — The N stems queried, oldest -> newest.
      - `stem` string, required — Filing-window stem.
      - `period_end` string, required — ISO date of quarter end.
      - `fetched_at` string, required — When this stem was ingested.
      - `filers_count` integer, required — Distinct filers in this quarter.
      - `holdings_count` integer, required — Total INFOTABLE rows after amendment dedup.
      - `notices_count` integer, nullable — Count of 13F-NT notices indexed for this quarter (B1).
    - `holders_added` Sec13fHolder[], required — In latest only.
      - `issuer` string, required
      - `title` string, required
      - `cusip` string, required
      - `figi` string, nullable
      - `value_usd_thousands` integer, nullable
      - `shares` integer, nullable
      - `shares_type` string, required
      - `put_call` string, nullable
      - `investment_discretion` string, required
      - `voting_sole` integer, required
      - `voting_shared` integer, required
      - `voting_none` integer, required
      - `accession` string, required
      - `period_of_report` string, required
      - `cik` string, required
      - `manager_name` string, required
    - `holders_removed` Sec13fHolder[], required — In earliest only.
      - `issuer` string, required
      - `title` string, required
      - `cusip` string, required
      - `figi` string, nullable
      - `value_usd_thousands` integer, nullable
      - `shares` integer, nullable
      - `shares_type` string, required
      - `put_call` string, nullable
      - `investment_discretion` string, required
      - `voting_sole` integer, required
      - `voting_shared` integer, required
      - `voting_none` integer, required
      - `accession` string, required
      - `period_of_report` string, required
      - `cik` string, required
      - `manager_name` string, required
    - `holders_changed` Sec13fHolderDelta[], required — In earliest+latest, value or shares differ.
      - `cik` string, required
      - `manager_name` string, required
      - `value_usd_thousands_from` integer, nullable
      - `value_usd_thousands_to` integer, nullable
      - `value_usd_thousands_delta` integer, nullable
      - `shares_from` integer, nullable
      - `shares_to` integer, nullable
      - `shares_delta` integer, nullable
    - `consensus_trend` Sec13fConsensusTrendPoint[], required — Per-stem aggregate count / value / shares across all N quarters, oldest -> newest.
      - `stem` string, required
      - `holder_count` integer, nullable — Holder count for this stem. Null when `available=false` because the underlying CUSIP shard failed to load (blob 404 / parse / network). Distinguishes 'shard unavailable' from 'legitimate zero holders'.
      - `total_value_usd_thousands` integer, nullable — Sum of reported value across holders. Null when `available=false`.
      - `total_shares` integer, nullable — Sum of share count across holders. Null when `available=false`.
      - `available` boolean — True when the underlying shard loaded successfully and the count / value / shares are real aggregates. False when shard load failed - count / value / shares are null in that case (prevents the prior false 'drop to zero' trend artifact).
  - `meta` SugraMeta, required — Metadata attached to every /api/v1/* response envelope.
    - `endpoint` string, required — Requested endpoint path.
    - `data_time` string, required — ISO 8601 UTC timestamp of the source data, not of the request.
    - `response_time` string, required — ISO 8601 UTC timestamp when this response was produced.
    - `provider` string, required — API name and version.
    - `source` string, nullable — Identifier of the primary upstream source used for this response.
    - `attribution` string, nullable — Human-readable attribution mandated by an upstream source (e.g. a securities regulator or self-regulatory organization). Present only on responses whose source requires the owner and source to be clearly identified. Do not remove or alter it when using the response.
    - `fallback_used` boolean, nullable — True when the primary source failed and a fallback produced the data.
    - `fallback_chain` string[], nullable — Ordered list of sources attempted, in the order they were tried.
    - `cached` boolean, nullable — True when this response was served from the internal cache.
    - `stale` boolean, nullable — True when the cached response was returned after the upstream rate-limited or errored. Clients can use this to detect degraded data.

## Other responses

- `401` — Missing or invalid `x-api-key` header. JSON body with a stable `code` distinguishing `missing_api_key` (no header sent) from `invalid_api_key` (header sent, key not accepted); any other 401 source carries the generic `unauthorized` with its detail as `reason`. Plus `hint`. `plan` is always null on 401 - an unauthenticated request has no plan; quota exhaustion is 429, not 401.
- `422` — Validation Error
- `429` — Daily rate limit exceeded. Check `X-RateLimit-Reset` for the next window.
- `503` — Upstream source is temporarily unavailable. Retry after a short delay.

---

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