Improver v Remington

Improver Corporation v Remington Consumer Product Limited (1990) is a leading United Kingdom case on patent infringement, particularly in relation to how to establish what specifically a patent covers. It set out a three-step test to establish whether a variant (alleged infringing article) infringes on an existing patent. The variant will not infringe if any of the following are true:The variant has a material effect on the way the invention works.The fact that the variant has no material effect on the way the invention works would not have been obvious to an expert in the field.That an expert in the field would have taken from the language used in the patent that its instructions should be followed in a strict literal fashion so as to exclude the variant.
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