(4) (5) The holder of the non-voluntary licence shall (a) have the right to exploit the patented invention in Mauritius according to the terms set out in the decision issuing the licence; (b) commence the exploitation of the patented invention within the time limit fixed in the said decision; and (c) thereafter, exploit the patented invention sufficiently. Where (a) the invention claimed in a patent (later patent) cannot be exploited in the country without infringing a patent granted on the basis of an application benefiting from an earlier filing or, where appropriate, priority date (earlier patent); and (b) the invention claimed in the later patent involves an important technical advance of considerable economic importance in relation to the invention claimed in the earlier patent; the Controller, upon the request of the owner of the later patent, may issue a nonvoluntary licence to the extent necessary to avoid infringement of the earlier patent. (6) Where a non-voluntary licence is issued under subsection (5), the Controller, upon the request of the owner of the earlier patent, shall issue a non-voluntary licence in respect of the later patent. (7) In the case of a request for the issuance of a non-voluntary licence under subsections (5) and (6), subsection (3) shall apply mutatis mutandis with the proviso that no time limit needs to be fixed. (8) In the case of a non-voluntary licence issued under subsection (5), the transfer may be made only with the later patent, or, in the case of anon-voluntary licence issued under subsection (6), only with the earlier patent. (9) The request for the issuance of a non-voluntary licence shall be subject to payment of a prescribed fee. (10) Sections 23(2) to 23(12) shall apply mutatis mutandis to a non-voluntary licence issued under this section. 25. Invalidation (1) Any interested person may request the Tribunal to invalidate a patent. (2) The Tribunal may invalidate the patent where the person requesting the invalidation proves that any of the requirements of sections 11,12 and 14 have not been fulfilled or where the owner of the patent is not the inventor nor his successor in title. (3) Any invalidated patent or claim or part of a claim shall be regarded as null and void from the date of the grant of the patent. (4) The final decision of the Tribunal shall be notified to the Controller who shall record it and publish a reference thereto as soon as possible.