This article explores Japanese transactional lawyers’ attempts to transplant American legal practice concerning corporate acquisition contracts into Japan. Despite their extensive efforts to disseminate legal concepts originating from the common law into the Japanese legal community, their transplantation attempts produced somewhat unexpected results by the promoters of the transplant. Faced with unfamiliar drafting styles and legal concepts, Japanese courts interpreted American-style corporate acquisition contracts in accordance with traditional Japanese-style contract interpretation. As a result, attempts by Japanese practitioners at transplantation were incomplete. This incompleteness is attributable to their inattention to the differences in approaches to contract interpretation between Japanese and New York courts. New York's approach is much more formalistic and literal than Japan's. If fully aware, however, they could have filled the gap by using functional substitutes for American techniques of controlling adjudicators’ contract interpretation which would effectively operate under Japanese law. Japan's experience confirms that a widely supported view in comparative law scholarship that transplanted law does not necessarily operate in the recipient jurisdiction as it did in its host jurisdiction is applicable to the transplantation of contract drafting practices.

Relational contract theory holds that the interpretation of a contract must take full account of the context and surrounding circumstances of the parties’ bargain so as to give effect to their respective intentions. This paper argues that if a relational treatment of contracts is to be institutionalised, in the sense of being utilised in a contract dispute to determine and give effect to the parties’ intentions, then it must operate at an abstract level. That is to say, rather than using relevant context to determine what the actual parties intended in the circumstances at hand, the contextualist enquiry should ascertain the relevant context by reference to what the parties would have agreed to in the circumstances, had they properly reflected on what their self-interest requires. I discuss the merits of this proposition by reference to a number of appellate judgments, which already endorse contextualism as a response to contractual ambiguity, and I ultimately apply it to the Supreme Court's judgment in Rainy Sky SA v Kookmin Bank.