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A party may not rely on a failure of the other party to perform, to the extent that such failure was caused by the first party's act or omission.
Art. 80 is new and was added at Vienna out of an abundance of caution. It states the self-evident proposition that a party cannot rely on another party's failure to perform if the failure was induced by the first party's own conduct e.g., by supplying faulty specifications for the construction of a machine or vessel or instructing the seller to use the paint of a particular manufacturer which proves unsuitable for the purpose for which it is intended.
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