Privacy
Last updated 13 November 2026
Controller
Artem Baranov, self-employed tax adviser, NIF [NIF], [address]. Contact: [email on sereno.tax].
What we process and why
| Your account | Name and email, to let you sign in. Basis: contract (GDPR art. 6.1.b). |
|---|---|
| Your documents | Invoices, receipts, tax returns and other papers you add, to prepare and file your tax obligations and the packs you ask for. Basis: contract (art. 6.1.b) and legal obligations (art. 6.1.c). |
| Identity checks | ID, address and source of funds, because tax advisers must know their clients under Spanish anti-money laundering law (Ley 10/2010). Basis: legal obligation (art. 6.1.c). |
| Access log | Sign-ins and every view of a document or a shared pack, to keep your papers safe and to show you who opened what. Basis: legitimate interest in security (art. 6.1.f). |
Software that reads your documents
An AI model reads each document to draft its fields and a short explanation. The draft is marked as such, and your adviser checks it before it counts. The model runs on Google Cloud in the European Union under a paid contract; your documents are not used to train it.
Who else handles your data
- Railway: hosting and database, EU region.
- Google Cloud (Vertex AI): document reading, EU region.
- Email provider for sign-in codes and reminders: [provider], EU region.
- Telegram, only if you choose to send documents through the Sereno bot.
When you share a pack, the person with the link sees the documents in it until the link expires or you switch it off.
How long we keep it
Tax documents are kept for as long as tax law allows them to be reviewed, and business records for as long as commercial law requires. Identity checks are kept for the period Ley 10/2010 sets. After that, data is deleted. [periods to confirm]
Your rights
You can ask for access, correction, deletion, portability, restriction or objection by writing to the contact above. You can also complain to the Spanish data protection agency (AEPD, aepd.es).
Cookies
One cookie keeps you signed in. It is strictly necessary, so there is no banner.