If the publication fee exceeds the limit of 2000 EUR (excl. VAT) a pro rata funding is impossible. We recommend that authors apply for a waiver or reduction in fees.

No. But make sure that invoices from European countries other than Germany give the price without value-added tax.

If an APC exceeds the 2000 EUR (excl. VAT) limit by a small amount and if that overrun is caused only by exchange-rate fluctuation, the article will not be excluded from funding.