I am dubious abut the above translation.

An “aufschiebende Bedingung” is a ‘condition precedent’ in legal terms (c.f aufLÖSENDE Bedingung which is a condition subsequent) see e.g. Hamblock/Wessels.

I assume the term comes from a contract selling receivables to a bank (perhaps some kind of factoring arrangement) and I think that, in this case, the condition precedent is the “Erfullung des Kaufpreises für die Forderung durch die Bank” i.e. the Lieferant assigns the receivable to the bank, and this assignment is documented in the contract but will only actually take place if the Bank has paid for the receivable, so a rough and ready translation would be something like (original German sentence structure retained here for clarity) -

“Subject to the condition precedent that the bank has paid the purchase price for the receivable/claim/account receivable to the supplier, the supplier hereby assigns said receivable to the bank, which accepts this assignment”