In a matter where there was a partly written and partly oral agreement, the court allowed evidence to be admitted regarding the terms of the oral agreement because it did not contradict nor vary the written agreements but rather supplemented them. The parol evidence rule applies where the written agreement is intended to be the exclusive recording of the agreement between the parties. If the written agreement is merely intended to record a portion of the transaction, leaving the remainder as an oral agreement, then the rule prevents the admission of other evidence only if it contradicts or varies the written portion. In this case the written agreements dealt with the delivery, purchase price and payment for certain equipment but did not deal with the question who bore the obligation to commission the equipment. The oral agreement regarding commissioning did not contradict nor vary the written agreements and the evidence was admissible.
It is because of these considerations that agreements commonly include a clause to the effect that the written document is the sole agreement between the parties regarding the matters dealt with in the agreement. That clause does not always preclude evidence regarding other oral agreements dealing with other issues.
These events began in 2010. One cannot help wondering whether the money spent on litigation over ten years could not have been used in the first place to commission the equipment. Contracting parties in a dispute should keep their eye on the outcome required.
[Traxys Africa Holdings Limited and Another v Westbrook Resources Limited  ZASCA 122 (23 September 2021)]