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Formal legal pages for YiChess, operated by Vistasense AI Technology Limited. Last updated May 31, 2026.

Open Source Notice

Last Updated: May 31, 2026

Product / brand: YiChess Product website: https://yichess.com Operator and seller-facing entity: Vistasense AI Technology Limited, a Hong Kong limited company, Company No. 80364727, Business Registration Certificate No. 80364727-000-05-26-8, registered address: Room 1602, 16/F, Wing On Centre, 111 Connaught Road Central, Hong Kong. Support: support@yichess.com

1. Open-Source Components

YiChess may use open-source software components, libraries, frameworks and tools.

2. Chinese Chess Engine Components

Certain chess engine analysis features may interact with Pikafish or other open-source Chinese chess engine components. Pikafish is open-source software and is not proprietary software of Vistasense AI Technology Limited or Hangzhou Weishi Information Technology Co., Ltd..

3. Licenses

Open-source components are subject to their own licenses, terms, notices and attribution requirements. Where required, license texts, notices, attribution, copyright statements or source-code access information will be made available.

4. No Warranty from Open-Source Contributors

Open-source contributors do not sponsor, endorse or control YiChess. Open-source components are typically provided without warranties under their applicable licenses.

5. Compliance Requests

For open-source compliance requests, contact legal@yichess.com. Please include the product page, component name, version if known and the nature of your request.