Section 64 of the Patents Act 1977 states:
64.-(1) Where a patent is granted for an invention, a person who in the United Kingdom before the priority date of the invention -(a) does in good faith an act which would constitute an infringement of the patent if it were in force, or (b) makes in good faith effective and serious preparations to do such an act, 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.
Frequently and in many fields, there is duplication of work as different people or teams are working on solving the same problem. This may occur because the problem to be solved is one suddenly and apparently needing solving, for instance carbon monoxide capture. In essence section 64 PA77 protects a contemporaneous invention that would ordinarily infringe a later granted patent (which we shall call P1). This second invention (which we will call P2) may not have been disclosed previously or a patent application may even have been filed before publication of P1.
First past the post is still the case, and the protection offered is for a person doing, or who has made ‘serious and effective preparation’ for the act that will later be infringing. This is a definition for case law and the court but colloquially speaking requires more than thinking hard about it. It is worth noting that s64 does not protect a person who files the P2 application a day after P1, even if both have proceeded to grant, as P1 was not published and therefore not citable against P2. The P2 owner is infringing unless he has prior use meeting s64 requirements. And he is rather unlucky. Do not delay filing is today’s lesson, as usual.
MUMMERY LJ delivered the judgment of the court. The Claimant had a genuine commercial interest in the revocation. It wished to know before it launched its product whether the Defendants could stop it from making or selling its product in the UK on the basis of the Patent. The lower court judge found that the claimant would suffer actual prejudice if there was delay in resolving the validity of the patent and Their Lordships did not think it was possible to fault that decision.