# Optimal Blue Loan Trading APIs (Resitrader)

**Canonical:** https://apis.io/apis/black-knight/optimal-blue-trading/  
**Provider:** Black Knight (Acquired by ICE — Now ICE Mortgage Technology) — https://apis.io/providers/black-knight/  
**Documentation:** https://digitalmarketplace.optimalblue.com

Optimal Blue Loan Trading APIs (Resitrader) is one of 9 APIs that [Black Knight (Acquired by ICE — Now ICE Mortgage Technology)](https://apis.io/providers/black-knight/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include Loan Trading, Resitrader, and Secondary Marketing. The published artifact set on APIs.io includes API documentation.

Workflow and data APIs for the Resitrader loan-trading application — execute trades, manage data modules, centralize trading operations. Now operated by Optimal Blue under Constellation Software ownership.

## Machine-readable artifacts (2)

- **DeveloperPortal** — https://digitalmarketplace.optimalblue.com
- **Documentation** — https://www2.optimalblue.com/api

## Other Black Knight (Acquired by ICE — Now ICE Mortgage Technology) APIs (8)

- [MSP DX (Direct Exchange) APIs](https://apis.io/apis/black-knight/msp-dx/)
- [Servicing Digital / Promise To Pay APIs](https://apis.io/apis/black-knight/servicing-digital/)
- [LoanSphere Default, Document & Decisioning Suite](https://apis.io/apis/black-knight/loansphere/)
- [Empower LOS APIs](https://apis.io/apis/black-knight/empower-los/)
- [Encompass Developer Connect (sibling product under ICE)](https://apis.io/apis/black-knight/encompass-developer-connect/)
- [Optimal Blue Product & Pricing APIs (divested to Constellation)](https://apis.io/apis/black-knight/optimal-blue-ppe/)
- [Optimal Blue Business Intelligence APIs](https://apis.io/apis/black-knight/optimal-blue-business-intelligence/)
- [Optimal Blue Broker Pricing APIs (Loansifter)](https://apis.io/apis/black-knight/optimal-blue-broker-pricing/)

## Tags

Loan Trading, Resitrader, Secondary Marketing

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/black-knight/optimal-blue-trading/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/black-knight/.