BGB §§ 286/288: B2B Entgeltforderungen accrue Basiszinssatz + 9 percentage points plus a single €40 Pauschale (§288 Abs.5). The Basiszinssatz (§247, published half-yearly by the Bundesbank) applies taggenau — each day accrues at the rate in force that day, so periods spanning 1 January / 1 July are split. This is not the ECB rate + 9 (a common error). Governing law is selected explicitly — never inferred from currency or location.
Scope in v1: business debtors, remuneration claims, EUR, obligations arising after 28 July 2014. Consumers, non-remuneration debts and earlier contracts are rejected with an explanation.
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