--- id: RISK-POL-0009 type: legal-policy title: "Commercial and tax retention" regime: "HGB §257, AO §147" status: active activates_when: "the estate keeps commercial books or issues and receives invoices — already true" owner: risk-nexus written: "2026-08-20" cadence: instant clean_streak: 0 last_checked: "2026-08-20T21:30:00Z" next_check: "2026-08-20T21:30:00Z" --- # RISK-POL-0009 — commercial and tax retention **Active now.** This is the one policy in the set that does not wait for a context: the estate already invoices, holds bank records and keeps books. ## What the sources require | Class | Period | Source | | --- | --- | --- | | Books, inventories, opening balance sheets, annual accounts, management reports | 10 years | §257(1) no. 1, (4) HGB; §147(1) no. 1, (3) AO | | Accounting vouchers (*Buchungsbelege*) | **8 years** | §147(3) AO, shortened from ten by the Fourth Bureaucracy Relief Act with effect from 2025 | | Commercial and business letters received and sent | 6 years | §257(2), (4) HGB; §147(1) nos. 2–3 AO | Periods run from the **end of the calendar year** in which the last entry was made or the document created — not from the document's own date. That detail is the one most often got wrong, and it always extends the period rather than shortening it. **The eight-year figure is recent and this repo has not verified it against the current text.** Confirm before relying on it for a deletion decision; ten years is the safe reading if nobody has. ## What it requires of systems - Records in these classes must be **retrievable for the whole period**, not merely undeleted. A backup nobody can restore from does not satisfy a retention duty — the same standard `RISK-F-0006` applies to `apps-pg`. - Immutability of content: they must not be silently rewritable. - Deletion must be **possible and deliberate** at the end of the period. Retention duty is a floor, not a licence; `RISK-POL-0002` supplies the ceiling. ## Where it collides With erasure (`RISK-POL-0002`, `RISK-F-0008`). An erasure request touching a record inside a statutory retention period does not defeat the duty — Art 17(3)(b) GDPR covers exactly this. But **the exemption is per record, not per system**: it covers the invoice, not the entire event log the invoice passed through. That distinction is where "we keep audit because it is audit" fails, and it is why `RISK-REG-0001` states periods per category rather than one figure. ## Evidence that would show this is met A retention schedule per record class; a demonstrated restore from the oldest retained period; a deletion routine that actually runs at expiry. None of those exist yet. This policy is `active` in the sense that the duty applies, not in the sense that it is demonstrably satisfied — and the register says which.