13F Holdings Comparison API — Quarter-over-Quarter Institutional Changes

Compare 13F institutional holdings quarter over quarter via API. Track new positions, exits, share changes, and portfolio turnover for any institutional investor. Start free.

13F Holdings Comparison API

Institutional investors file 13F reports every quarter, but the real signal is in what changed. Datastream’s comparison endpoint diffs two quarters of 13F data automatically — surfacing new positions, exited positions, increased holdings, and decreased holdings without you having to compute the diff yourself.

Capabilities

Automatic quarter diff

Compare any two quarters for a 13F filer in a single request. New, exited, increased, and decreased positions returned separately.

Share and value changes

Both absolute and percentage changes in shares and market value for every position that changed.

Portfolio-level metrics

Total portfolio value, position count, turnover rate, and concentration metrics for each quarter.

Multi-filer comparison

Compare holdings across multiple filers to find stocks being accumulated (or dumped) by the smart money simultaneously.

Quick start

Compare Bridgewater’s holdings between Q3 and Q4 2024:

curl -H "x-api-key: $OMNI_DATASTREAM_API_KEY" \
  "https://api.secapi.ai/v1/owners/13f/compare?cik=0001350694&period_a=2024-Q3&period_b=2024-Q4"

{
  "manager": "BRIDGEWATER ASSOCIATES, LP",
  "period_a": "2024-Q3",
  "period_b": "2024-Q4",
  "new_positions": [
    {
      "issuer_name": "NVIDIA CORP",
      "cusip": "67066G104",
      "shares": 5200000,
      "value": 720000000
    }
  ],
  "exited_positions": [
    {
      "issuer_name": "INTEL CORP",
      "cusip": "458140100",
      "shares_sold": 12000000
    }
  ],
  "increased": 145,
  "decreased": 89,
  "portfolio_turnover": 0.23
}

Use cases

Smart money tracking

Monitor what the top hedge funds and asset managers are buying and selling each quarter. Identify consensus trades across multiple filers.

Crowded trade detection

Find stocks where many institutions are building positions simultaneously — a potential crowded trade signal.

Portfolio rebalancing signals

Use quarter-over-quarter changes from top managers as an input signal for systematic or discretionary strategies.

Client reporting

Wealth managers can generate reports showing how major institutional investors are positioning relative to client portfolios.

API endpoints

Endpoint	Description
GET /v1/owners/13f/compare	Compare two quarters for a filer
GET /v1/owners/13f	List holdings for a specific quarter
GET /v1/owners/13f/top-changes	Biggest position changes across all filers

Why Datastream for 13F comparison

Feature	Datastream	Raw EDGAR	WhaleWisdom	Fintel
Built-in quarter diff	Yes	No (manual)	Manual	Manual
Share + value changes	Yes	Manual calc	Partial	Partial
Portfolio turnover metrics	Yes	No	No	No
Multi-filer aggregation	Yes	No	Premium	Premium
REST API	Yes	No	No	Limited
Pricing	Pay-as-you-go	Free (raw)	$150+/mo	$100+/mo

Get started

Get your API key

Start comparing institutional holdings in under 60 seconds. 250 free API calls per month.

• 13F Institutional Holdings API
• Insider Trading API
• API Reference