Cases - Crosfield (Joseph) and Sons Ltd v Techno-Chemical Laboratories Ltd

Record details

Name

Crosfield (Joseph) and Sons Ltd v Techno-Chemical Laboratories Ltd

Date

[1913]

Citation

29 Times Law Reports 378, ChD

Keywords

Expert witness

Summary

In a patent action concerning chemical compounds, the judge set out the purposes of calling expert witnesses in such cases, noting that there is no difference in regard to admissibility between patent cases and others.

'The assistance of expert evidence in patent actions is generally essential. It is required for the purpose of explaining words, or terms of science or art, appearing in the documents which have to be construed by the Court, or to inform the Court in case the import of a word or phrase differs from its popular meaning. Further than this, in some cases it is impossible for the Court to understand a document without instruction with regard to the laws of science with which the patent may be concerned without expert assistance. Moreover, the Court cannot inform itself as to the state of public knowledge with regard to the matters in question at the date of the patent.'

The court also expressed the view that it was not permissible for experts to give their opinions on the law or on matters in issue.

This last point is sometimes referred to in modern cases as the 'ultimate issue'. However, the latter approach has been modified in a number of subsequent cases: see Barings v Coopers & Lybrand and Midland Bank v Hett Stubbs & Kemp.