Privacy Policy
Last updated: March 2026
1. Information We Collect
We collect minimal information necessary to operate the platform:
- Wallet address your public Ethereum address, used for authentication via Sign-In with Ethereum (SIWE).
- Trade data records of your trades, orders, positions, and balances on the platform.
- Comments any comments you post on market discussion threads.
- Usage data page views, actions taken, and timestamps for platform improvement.
We do not collect email addresses, names, phone numbers, or any personal identification information unless you voluntarily provide it.
2. How We Use Your Information
- To authenticate your identity via your wallet signature.
- To execute and record trades on the blockchain.
- To display your positions, P&L, and trade history.
- To show public market data (top holders, activity feeds).
- To improve the platform and fix bugs.
3. Data Storage
Your data is stored on our servers and on the Polygon blockchain. Trade data is logged in CSV and JSON format on the server. Blockchain transactions are permanent and publicly visible. We use PostgreSQL for structured data when available, with file-based fallbacks.
4. Public Information
The following information is publicly visible to all users:
- Your wallet address (truncated in the UI).
- Your positions and trade history on each market.
- Comments you post on market discussion threads.
- Your ranking on the leaderboard (if applicable).
5. Cookies and Local Storage
We use browser local storage to save your JWT authentication token, theme preference, and onboarding status. We do not use third-party tracking cookies. No analytics services (Google Analytics, Mixpanel, etc.) are currently integrated.
6. Third-Party Services
We interact with the following external services:
- Polygon Network for on-chain trade execution.
- CoinGecko API for live cryptocurrency price data.
- Polymarket API for displaying external market reference data.
7. Data Retention
Trade logs are retained indefinitely for audit and transparency purposes. Comments and activity data are retained for as long as the platform operates. You may request deletion of your comments by contacting support.
8. Your Rights
You have the right to view all data associated with your wallet address through the portfolio and profile pages. Since we do not collect personal identification information, traditional data subject rights (GDPR, KVKK) may have limited applicability. Contact us if you have questions about your data.
9. Contact
For questions about this privacy policy, contact us via our social media channels or through the Help page.
Privacy on Kayxa
Kayxa is a decentralized prediction market platform built on Polygon blockchain. Because all market trades are executed by the Kayxa admin wallet on-chain, your individual trade history is not publicly linked to your wallet address on the blockchain. Your off-chain USDC balance, position history, and account details are stored in a private PostgreSQL database accessible only to the Kayxa team. We do not sell or share your personal data with third parties for advertising purposes.
When you sign in with email, we store your email address to authenticate your account and send transactional notifications such as market resolution results and deposit confirmations. When you connect a Web3 wallet, we store your wallet address to link your on-chain deposits and withdrawals to your account. We use standard session cookies to keep you signed in. We do not use tracking cookies or third-party ad networks. Analytics are collected in aggregate to understand platform usage and improve features.
Kayxa does not require KYC (Know Your Customer) identity verification to trade. You can browse all markets, view prices, and read the order book without creating an account. An account is only required to deposit funds and place trades. You may request deletion of your account and associated personal data by contacting us through the Help page. On-chain transactions recorded on Polygon are permanent and cannot be deleted, as they are part of a public blockchain ledger.
We take security seriously. Passwords are hashed using industry-standard bcrypt. API endpoints are protected with JWT tokens. Our database is not publicly accessible. We use HTTPS for all connections. If you discover a security vulnerability in Kayxa, please report it responsibly through our contact page. For full details on how we handle your data, read the complete privacy policy above or contact us via the Help page.