> This page is for Web API.

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://ibkrcampus.com/docs/llms.txt.

# IBKR WebAPI

* [Authentication for Client Portal Gateway](/docs/web-api/authentication/cpgw/installation-authentication) has been updated to better indicate the need for [Session Initialization](/docs/web-api/api-reference/trading/trading-session/initialize-session).
* Documentation for [`/v1/api/sso/validate`](/docs/web-api/v1/endpoints/session/validate-sso) has been updated to reflect `EXPIRES` property behavior.
* The Client Portal Gateway has been updated to correctly block LITE account and Fractional order submissions and will be reflected in production beginning October 30, 2026.