Section 64 of the UK patents act provides prior users with a
personal defence in recognition that it would be wrong if patents
were allowed to be used to prevent a person from carrying on an
activity that they were doing prior to grant (the so-called right to
work doctrine).
The prior acts must be committed in the UK and only available
where the acts were carried out in good faith. The defence is only
available where, the defendant has done the acts or made ‘serious
and effective preparations’ before the priority date of the patent to
do an act which would be infringing if it was carried out after the
grant of the patent.
Lubrizol v Esso: The preparations must be so advanced as to be
about to result in the infringing act being done.
The same person has the right to continue to do the act or, as the
case may be, to do the act, notwithstanding the grant of the patent;
but this right does not extend to granting a licence to another
person to do the act.
Nothing on this site constitutes legal advice, an offer, an offer to treat or a legal relationship.
Always check with your IP consultant.
