> ## Documentation Index
> Fetch the complete documentation index at: https://docs.kraken.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Institutional overview

> OTC trading, custody, and prime brokerage APIs — designed for institutions managing large positions or client assets

Kraken's Institutional platform covers four distinct services, each purpose-built for a specific use case. Access to all Institutional APIs requires onboarding through your Kraken Account Manager.

## Services overview

| Service             | What it does                                                                     | Protocol  |
| :------------------ | :------------------------------------------------------------------------------- | :-------- |
| **OTC**             | Execute large block trades off the order book with minimal market impact         | REST      |
| **Custody**         | Secure digital asset storage with segregated accounts, deposits, and withdrawals | REST      |
| **Prime FIX**       | Low-latency institutional order management via FIX 4.4                           | FIX 4.4   |
| **Prime WebSocket** | Real-time market data, order updates, and account event streaming                | WebSocket |

## What can I build?

<CardGroup cols={2}>
  <Card title="Block trading desk" icon="handshake">
    Use the **OTC REST** API to request quotes and execute large trades at negotiated prices, avoiding slippage on the public order book. Suitable for single-asset and cross-asset block trades.
  </Card>

  <Card title="Institutional custody" icon="vault">
    Use the **Custody REST** API to manage segregated wallets, automate deposit monitoring, initiate withdrawals, and reconcile client balances programmatically.
  </Card>

  <Card title="Prime order management" icon="terminal">
    Use **Prime FIX** for deterministic, low-latency order routing with cancel-on-disconnect, session-based message replay, and co-location at Equinix London. Designed for systematic and HFT workflows.
  </Card>

  <Card title="Real-time prime data" icon="bolt">
    Use **Prime WebSocket** to stream live order book data, fills, open positions, and account balances into your own execution or risk systems.
  </Card>
</CardGroup>

## Choosing your protocol

| Need                                     | Use                         |
| :--------------------------------------- | :-------------------------- |
| Large off-book trade at a specific price | OTC REST                    |
| Programmatic custody and asset movement  | Custody REST                |
| Low-latency order management with replay | Prime FIX                   |
| Real-time fills and position data        | Prime WebSocket             |
| Combined order entry + data streaming    | Prime FIX + Prime WebSocket |

## Getting started

All Institutional API access requires onboarding. Contact your Account Manager or reach out at [institutional@kraken.com](mailto:institutional@kraken.com) to:

* Request API credentials for the services you need
* Arrange co-location if using Prime FIX
* Complete any required NDA or compliance documentation

<CardGroup cols={2}>
  <Card title="Custody REST authentication" icon="lock" href="/institutional/guides/custody-rest-auth">
    How to authenticate requests to the Custody REST API
  </Card>

  <Card title="Prime WebSocket authentication" icon="lock" href="/institutional/guides/prime-websocket-auth">
    How to authenticate and subscribe to Prime WebSocket channels
  </Card>
</CardGroup>