FillBook
Privacy Policy
- Effective
- July 19, 2026
- Operator
- FillBook
FillBook is a trade journal, so — unlike a stateless tool — it does store data you give it. This page is a plain-English account of exactly what we keep, why, and how to get rid of it. We do not sell your data, and we never place trades.
What we store
Your account (email, and name/avatar if you sign in with Google). Your imported trading data: fills, positions, realized P&L, and the Kalshi API key you connect. Your journal content: the notes and tags you write on positions. That's it.
Your venue credentials
Kalshi: we ask only for a read-scoped API key, and we encrypt its private key at rest (AES-256-GCM). We can read your fills and settlements; we cannot place or cancel orders.
How we use it
Solely to run the product for you: importing and normalizing your trades, computing analytics, and showing your journal. We do not use your trading data to train models, and we do not share or sell it to anyone.
Third parties
We rely on a small set of processors: a database host (Neon), our app host (Vercel), an email provider for magic-link sign-in, and a payment provider for Pro subscriptions. The payment provider handles your card details — we never see them. Each processor only receives what it needs to do its job.
Marketing-page analytics
On our public marketing pages only — the landing page, the live demo (which shows sample data, not real accounts), and similar — we use Microsoft Clarity to understand how visitors interact with the page so we can improve it. Clarity is deliberately never loaded inside the app or on any page that shows your account, positions, P&L, or journal, so your trading data is never recorded or sent to it. It also masks text by default.
Cookies
Inside the app we use a single first-party session cookie to keep you signed in. On our public marketing pages, Microsoft Clarity sets analytics cookies to measure how the page is used — these are not advertising cookies, and they never run on pages that contain your data.
Deletion
Disconnect a venue in the app and we delete that venue's imported data immediately. Want your entire account and all data erased? Email us and we'll delete it, no questions asked.
Changes
If this policy changes materially, we'll update the effective date and, for account-holders, notify you by email.
Contact: support@fillbook.io