Contract and property law are traditionally seen as rather distinct parts of a legal system. However, there is growing awareness that contract and property are not so separate at all. We can observe more and more fuzzy boundaries. Four examples (case studies) are discussed: reclaiming money, the non-accessory mortgage, protection of mortgagors, private re-registration of mortgages in the us: mortgage electronic registration systems (mers). The fuzzy boundaries make us realise that the distinction between contract and property (in the classical, 19th century, model of private law: the absence or presence of the binding force of an arrangement on third parties) is becoming less of a binary division and more of a gradual nature. It seems that ...