IP-2024-000024 - [2025] EWHC 492 (IPEC)

The experts were agreed that the terms ‘sleeve’ and ‘sheath’ are sometimes used interchangeably. The skilled reader of the Patent would not rely on ‘sheath’ as a term of art to distinguish such a thing from a sleeve. Whether there is a relevant difference between the sleeve of Soble and the sheath of the Patent depends on the respective ways in which each is used.

Mr Saeb-Parsy for Well Lead identified three distinctive features of the Soble sleeve that would not make it suitable for use as a sheath in the invention of the Patent: the Soble sleeve covers the scope completely, it moves in tandem with the scope and it fits the scope snugly. None of these distinctions survived in cross-examination. Professor Somani said that there was no relevant distinction between the Soble sleeve and the sheath of the Patent and he maintained this in cross-examination. I accept Professor Somani’s evidence on this.