所有权保留,是指在支付全部价款之前,标的物已由出卖人移转至买受人占有的交易中,待买受人支付全部价款之前,出卖人保留标的物的所有权。换句话说,即使作为其根本原因的债权行为与物权行为完成了标的物的让渡,根据所有权保留特约,所有权没有发生转移,只有支付所有价款,所有权才能转移到买受人。如今,这类所有权保留主要用于洗衣机、钢琴等商品,即动产的买卖。但是,所有权保留不仅限于动产,还涉及土地或建筑物等不动产的分期付款。因出卖人自合同成立就让渡标的物,所以即使是双 Retention of ownership means that the subject matter has been transferred from the seller to the buyer before the full price is paid and the seller retains the ownership of the subject matter until the buyer pays the full price. In other words, even if the transfer of the subject matter is completed as the underlying cause of the claims and the acts of the property, no transfer of ownership occurs under the reservation of ownership, and only the payment of all the proceeds can the ownership be transferred to the buyer. Today, this type of ownership is reserved primarily for the sale of goods such as washing machines, pianos and the like. However, the retention of title is not limited to movable property but involves the payment of installments of real property such as land or buildings. Because the seller set up the contract from the transfer of the subject matter, so even if the double