Terms of Use
Last Updated: March 4th, 2026
These Terms of Use (“Terms”) govern your access to and use of the website, products, and services provided by Yanssie HK Limited, the operator of the Keystone brand (“Company”, “we”, “our”, or “us”).
By accessing or using our website, products, or services (collectively, the “Services”), you agree to be bound by these Terms. If you do not agree to these Terms, you should not access or use the Services.
1. Eligibility
You must be at least 18 years old to access or use the Services.
By using the Services, you represent and warrant that:
- You are at least 18 years of age.
- You have not been previously suspended or removed from the Services.
- Your use of the Services complies with all applicable laws and regulations.
If you access the Services on behalf of a company or organization, you represent that you have the authority to bind that entity to these Terms.
2. Description of Services
Keystone provides hardware wallet devices, firmware, software tools, and related services designed to enable users to securely manage digital assets.
Keystone hardware wallets allow users to:
- Generate or import recovery phrases (seed phrases) within the device environment
- Derive and manage wallet addresses for supported blockchain networks
- Receive digital asset transfers by providing associated public addresses
- Display and present transaction details for user verification prior to signing
- Sign transaction data using private keys stored within the device
- Export signed transaction data for broadcasting through compatible software wallets
- Protect locally stored information through password protection, pattern locks, or supported biometric authentication mechanisms
- Install firmware updates to maintain device functionality and security features
- Initiate the transaction and sign it with Keystone Nexus
The Services may also include firmware updates, documentation, developer tools, and compatibility with third-party wallet applications.
3. Non-Custodial Nature of Services
Keystone products operate under a non-custodial architecture.
This means:
- We do not store cryptocurrencies.
- We do not control blockchain transactions.
- We do not have access to private keys or recovery phrases.
All blockchain transactions are executed directly on blockchain networks and are controlled exclusively by the user.
You are solely responsible for managing your wallet credentials, including private keys and recovery phrases.
Loss of recovery phrases or private keys may result in permanent loss of digital assets, which cannot be recovered by the Company.
4. User Responsibilities
You are solely responsible for:
- Safely storing your recovery phrase
- Securing your hardware wallet device
- Verifying transaction details before signing
- Protecting your device and private keys from unauthorized access
The Company cannot restore or recover lost private keys, passwords, or recovery phrases.
5. Supported Networks and Third-Party Services
Keystone products may support various blockchain networks and integrate with third-party wallet software or applications.
These networks and services are not operated or controlled by Yanssie HK Limited.
We make no guarantees regarding:
- the availability of blockchain networks
- the functionality of third-party wallets
- compatibility with future blockchain protocol changes
Use of third-party services is subject to their respective terms and policies.
6. Open Source and Firmware Modification
Certain components of Keystone firmware or software may be released under open-source licenses.
Users may review, modify, or compile open-source components in accordance with the applicable licenses.
However:
- Unauthorized modification of firmware may affect device security.
- Devices running modified firmware may not function as intended.
- The Company is not responsible for any loss resulting from modified firmware or unofficial software builds.
7. Export Controls and Sanctions Compliance
The Services may be subject to export control laws and regulations.
By using the Services, you represent and warrant that:
- You are not located in a country subject to international sanctions or export restrictions.
- You are not listed on any government sanctions list or restricted persons list.
You agree to comply with all applicable export control laws.
8. Prohibited Conduct
You agree not to:
- Use the Services for illegal activities.
- Attempt to reverse engineer or exploit the Services beyond what is permitted by law.
- Upload or distribute malicious software.
- Interfere with the operation or security of the Services.
- Attempt to bypass security mechanisms.
9. Risk Disclosure
Cryptocurrency assets involve significant risk.
You acknowledge that:
- Blockchain transactions are irreversible.
- Cryptocurrency markets are highly volatile.
- Blockchain networks may experience failures, forks, or attacks.
The Company does not provide financial, legal, or investment advice.
You should conduct your own research and seek professional advice before engaging in cryptocurrency transactions.
10. Disclaimer of Warranties
Except as otherwise stated in the hardware warranty policy, the Services are provided “as is” and “as available.”
To the maximum extent permitted by law, we disclaim all warranties including:
- merchantability
- fitness for a particular purpose
- non-infringement
- uninterrupted or error-free operation
11. Limitation of Liability
To the fullest extent permitted by law, Yanssie HK Limited shall not be liable for any damages arising from:
- loss of digital assets
- loss of private keys or recovery phrases
- unauthorized access to user wallets
- blockchain network failures
- software bugs or vulnerabilities
- third-party attacks such as phishing or malware
In no event shall our total liability exceed the amount paid for the applicable product.
12. Indemnification
You agree to defend and indemnify Yanssie HK Limited and its affiliates from any claims or liabilities arising from:
- your use of the Services
- your violation of these Terms
- your violation of any third-party rights
13. Hardware Warranty (Keystone Care+)
Keystone hardware wallets include a 1-year limited warranty starting from the date of delivery.
Customers may optionally purchase extended Keystone Care+ protection plans:
- 2-Year Keystone Care+ — $50 USD
- 3-Year Keystone Care+ — $100 USD
The warranty covers manufacturing defects under normal use.
The warranty does not cover:
- physical damage
- misuse or improper handling
- modified firmware
- environmental damage
- natural disasters
The warranty is non-transferable and applies only to the original purchaser.
This updated warranty policy takes effect January 1, 2025.
Products purchased before this date follow the previous 2-year warranty policy.
14. Governing Law
These Terms are governed by the laws of the Hong Kong Special Administrative Region.
Any disputes arising from these Terms shall be submitted to the exclusive jurisdiction of the courts located in Hong Kong SAR.
15. Changes to These Terms
We reserve the right to modify these Terms at any time.
Continued use of the Services after updates constitutes acceptance of the revised Terms.
16. Contact
For questions regarding these Terms, please contact: