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PaperTax

Trust & privacy

How your data flows

Tax data is sensitive. Here's the full, specific picture: what we store, where it's processed, what we can see, and where the AI can be wrong.

The flow, step by step

  1. 01

    You upload

    PDF, JPG, or PNG from your device

  2. 02

    Stored in Switzerland

    Held in the Zürich region, encrypted at rest

  3. 03

    Read in the United States

    To read your document, it's sent to Anthropic's Claude in the US. Your data leaves Switzerland while it's being processed. Anthropic is contractually committed not to train on it.

  4. 04

    Your guide

    Structured entries appear in your return, one document at a time. It's guidance for you to check, not a filed return.

  5. 05

    Deleted on finish

    All uploads, chat, and guide data are erased within 24 hours of you marking the return done

Who touches your data

Four services, each with a specific role and retention policy.

  • Supabase

    Database + file storage, Zürich (Switzerland) region

    Deleted within 24 hours of finishing your return

  • Anthropic (Claude Agent)

    Reads your documents and generates your guide. Processed in the United States.

    Contractually committed not to train on your data. May retain API inputs up to 30 days for safety monitoring, per Anthropic's commercial terms.

  • Vercel

    Web application hosting and compute, Frankfurt (EU) region

    Standard request logs, no user content

  • Stripe

    Payment processing: card and bank details go directly to Stripe

    We only see a payment ID; card data never reaches our servers

Encrypted, but not end-to-end

Your files are encrypted while they sit in storage, but not end-to-end. They're unencrypted while the app and its AI read them — the only way an AI tool can work with your documents — and we hold the encryption keys. Each user's data is kept isolated from every other account.

An aid, not a guarantee

PaperTax gives specific, line-by-line guidance, but it is not a guarantee. It can miss a complex deduction or misread a document. We run a second automated check on the finished guide to catch inconsistencies, and you review every entry before you file. If your situation is complex or high-stakes, verify it against your documents or ask a tax advisor. You submit the return yourself, so nothing is filed without you.

Our commitments

  • Your files are stored in Switzerland and deleted within 24 hours of finishing your return
  • To read your documents, they're processed by Anthropic in the United States, so your data leaves Switzerland while it's being read
  • Anthropic has contractually committed not to train its AI models on your data, and we never train on it either
  • You submit your return yourself in your cantonal tax app. We never touch it
  • You can export or delete your entire return at any time
  • We don't share data with tax authorities or any third party beyond our sub-processors (Supabase, Anthropic, Vercel, Stripe)

Your data rights

Under Swiss and EU data protection law, you have the right to access, export, correct, and delete your data. Every active return has a privacy card showing exactly what's stored and how to remove it. For historical returns or anything unclear, email contact@papertax.ch.

Contact

Security concerns, incident reports, or data requests: contact@papertax.ch