Privacy Policy

I. Introduction

1. This Privacy Policy describes how data is processed and protected when you use KSeF Connect (the "App") — a Stripe App installed on your Stripe account that submits invoices issued in Stripe to Poland's National e-Invoicing System (KSeF), operated by the Polish Ministry of Finance.
2. The App is operated by the entity identified in Section II (the "Operator" or "we").
3. The user (the "Merchant") is a business that installed the App on its Stripe account to submit its own invoices to KSeF.

II. Data controller

1. The Operator of the App and the controller of the Merchant's data is: Sadowski Development Maciej Sadowski, ul. Obrońców Ojczyzny 41, 26-670 Pionki, Poland, NIP: 7962891514, REGON: 364118432.
2. Contact for all privacy and support matters: support@ksef-connect.pl.

III. Controller and processor roles

1. Merchant account data (e.g. NIP, business details, address, contact, billing data) — the Operator is the controller of this data and processes it to provide the service and handle billing.
2. Invoice and buyer data the Merchant submits — the Merchant is the controller. The Operator acts as a processor, processing it solely to submit invoices to KSeF on the Merchant's instructions.
3. Once an invoice is accepted by KSeF, the Ministry of Finance / National Revenue Administration becomes the controller of that data within KSeF, under applicable law.

IV. Data we process

1. Stripe account data: Stripe account ID (acct_…), business name, mode (test/live).
2. Seller details for invoices: NIP, name, address (street, number, postal code, city) — entered manually or fetched from the CEIDG registry by NIP.
3. KSeF credentials: KSeF certificate (.crt/.pem), private key (.key) with its password, or a KSeF authorization token. Stored encrypted only (see Section VIII).
4. Stripe OAuth tokens: access and refresh tokens enabling invoice access — stored encrypted.
5. Invoice and buyer data read from Stripe: invoice number, line items, amounts, currency, dates, and buyer details (name, address, NIP) — used to build the structured FA(3) invoice and submit it to KSeF.
6. Submission records: KSeF reference number, official confirmation of receipt (UPO), status, error messages and timestamps.
7. Usage and billing data: the number of invoices submitted in a given month (for billing).

V. Purposes and legal bases

1. Providing the service (Art. 6(1)(b) GDPR): installation, configuration, submitting invoices to KSeF, writing the KSeF reference back to the Stripe invoice.
2. Legal obligations (Art. 6(1)(c) GDPR): the Operator's tax/accounting obligations and — for the Merchant — the KSeF e-invoicing obligation.
3. Legitimate interest (Art. 6(1)(f) GDPR): security, error diagnostics, establishing and defending claims.

VI. Stripe permissions (OAuth scopes)

The App requests the minimum permissions on the Merchant's Stripe account needed to provide the service:

1. invoice_read — read invoices in order to submit them to KSeF;
2. invoice_write — write the KSeF reference number to the invoice metadata after a successful submission;
3. customer_read — read buyer data (name, address, NIP) required by the Podmiot2 section of the FA(3) invoice;
4. credit_note_read — read credit notes in order to issue correction invoices (FA-KOR).

VII. Recipients and sub-processors

Data may be shared only with parties necessary to deliver the service:

1. Stripe (Stripe Payments Europe / Stripe, Inc.) — the source platform for invoices and the processor for subscription billing.
2. Polish Ministry of Finance — KSeF — invoices are submitted to the National e-Invoicing System (this is the core purpose of the service and a legal requirement).
3. CEIDG (Central Registration and Information on Business) — a public registry queried by NIP to fill in seller details.
4. Hosting provider — the server infrastructure on which the App runs (webio.pl, servers in Poland).

Beyond the above, the Operator does not share data with third parties for marketing or analytics purposes.

VIII. Data security

1. Encryption at rest: KSeF credentials (certificate, private key, password, token) and Stripe OAuth tokens are stored in the database in encrypted form only (ASP.NET Core Data Protection). The certificate private key is used only server-side to sign the KSeF authentication request and is never disclosed.
2. Encryption in transit: all connections to the App use TLS (HTTPS).
3. Access control and monitoring: only authorized persons can access data; system logs are kept for security and diagnostics.

IX. Data retention

1. KSeF credentials and OAuth tokens are kept while the App is installed. When the App is uninstalled, access tokens are deleted and the account is deactivated.
2. Submission records (KSeF references, UPO) may be retained for the period required by tax law and the limitation period for claims.
3. To request full erasure of your data, contact support@ksef-connect.pl.

X. Your rights

You have the right to access, rectify, erase, restrict, port and object to the processing of your data, and to lodge a complaint with the President of the Personal Data Protection Office (PUODO). To exercise your rights: support@ksef-connect.pl.

XI. Transfers outside the EEA

To the extent Stripe processes data outside the European Economic Area, it does so under GDPR safeguards (including Standard Contractual Clauses). Invoices are submitted to KSeF on the Ministry of Finance's servers in Poland.

XII. Changes to this Policy

The Operator may update this Policy. Material changes will be communicated through the App or by email.