If the buyer has purchased a defective item and installed it in another item or attached it to another item as intended, he can demand compensation from the seller for the costs incurred by removing the defective item and reinstalling a replacement item as part of subsequent fulfilment (Section 439 (3) BGB). Fault on the part of the seller is not required for this claim for reimbursement of expenses. The costs can be considerable in individual cases and far exceed the purchase price. These economic risks for sellers have increased with the current ruling of the BGH of 21 June 2023 (case no. VIII ZR 105/22), as the BGH has thus significantly expanded the scope of application of the no-fault claim for reimbursement of expenses.