Contract

It had been common practice for the Commercial Court to hear evidence of “market practice”, which did not amount to evidence of an alleged “trade usage or custom”, in order to assist the court with a full understanding of the factual background to the proper construction of a written contract.

Therefore, evidence of the factual background known to the parties at and before the date of the contract, including evidence of the “genesis” and objectively the “aim” of the transaction, but not of negotiations, was admissible. If expert evidence was admissible to provide the background against which to construe a wholly written contract, including the exercise of construction which involved determining whether there was an “implied term”, then it seemed that the same exercise had to logically be permissible in the case of construing a partly written and partly oral contract.

What the parties agreed, expressly or implicitly, could only be judged against the factual background they knew, which had to include practices