—(1) Subject to the provisions of this Act, the Registrar may, on the application of any person, by order revoke a patent for an invention on (but only on) any of the following grounds:
the invention is not a patentable invention;
the patent was granted to a person who was not entitled to be granted that patent;
the specification of the patent does not disclose the invention clearly and completely for it to be performed by a person skilled in the art;
the matter disclosed in the specification of the patent extends beyond that disclosed —
in the application for the patent, as filed; or
where the patent was granted on a new application filed under section 20(3) or 47(4) or section 116(6) of the Patents Act (Cap. 221, 1995 Ed.), or in accordance with section 26(11), in —
the earlier application made under this Act;
the application made under the United Kingdom Patents Act 1977; or
the application under the European Patent Convention designating the United Kingdom filed at the European Patent Office,
as the case may be, from which the filing date and the right of priority has been derived, as filed;
an amendment or a correction has been made to the specification of —
the patent; or
the application for the patent,
which should not have been allowed;
the patent was obtained —
on any misrepresentation; or
on any non-disclosure or inaccurate disclosure of any prescribed material information, whether or not the person under a duty to provide the information knew or ought reasonably to have known of such information or the inaccuracy;
the patent is one of 2 or more patents for the same invention having the same priority date and filed by the same party or his successor in title.
(2) On the application of any person for an order to revoke a patent on any of the grounds specified in subsection (1)(a), (c), (d) and (e), the Registrar may, subject to subsection (3), cause the patent to be re-examined by an Examiner so as to determine whether the patent should be revoked on any of those grounds and require the applicant to pay the prescribed re-examination fee.
(3) The Registrar shall not cause a patent to be re-examined under subsection (2) where, within the prescribed period, the applicant for the revocation of the patent fails to give such security for the costs or expenses of the proceedings as the Registrar may specify; in which case, the application for revocation shall be treated as having been abandoned.
(4) An application for the revocation of a patent on the ground mentioned in subsection (1)(b) —
may only be made by a person found by the court in an action for a declaration or found by the court or the Registrar on a reference under section 47, to be entitled to be granted that patent or to be granted a patent for part of the matter comprised in the specification of the patent sought to be revoked; and
may not be made if that action was commenced or that reference was made after the end of the period of 2 years beginning with the date of the grant of the patent sought to be revoked, unless it is shown that any person registered as a proprietor of the patent knew at the time of the grant or of the transfer of the patent to him that he was not entitled to the patent.
(5) An order under this section may be —
an order for the unconditional revocation of the patent; or
(6) A decision of the Registrar or on appeal from the Registrar shall not estop any party to any civil proceedings in which infringement of a patent is in issue from alleging invalidity of the patent on any of the grounds referred to in subsection (1), whether or not any of the issues involved were decided in the decision.
(7) An order under this section revoking a patent shall have effect from the date of the grant of the patent.
(8) Where an applicant for the revocation of a patent discontinues or withdraws his application, he shall pay such costs or expenses of the proceedings as the Registrar may determine.
(9) An application for an order to revoke a patent shall be —
made in the prescribed form and filed at the Registry in the prescribed manner; and
accompanied by the prescribed fee.
(10) Section 92 shall not apply in relation to the decision of the Registrar to cause a patent to be re-examined under this section.
[UK Patents 1977, s. 72]