24 CAP. 400] Patents months. may allow. or•. with the consent of the applicant. at any time before the sealing of the patent. oppose the grant of a patent in accor­ dance with the provisions of this section by giving written notice to the Registrar of opposition to such grant on any of the following grounds and no others. namely: (a) that the applicant is not a person entitled under section eleven to make the application; (b) that the application is in fraud of the rights of the person giving such notice or of any persons under or through whom he claims; (c) that the invention does not relate to an art (whether pro­ ducing a physical effect or not). process, machine, manu­ facture or composition of matter, which is capable of being applied in trade or industry; (d) subject to the provisions of section thirty-one, that the invention is obvious in that it involves no inventive step having regard to what was common knowledge in the art at the effective date of the application; (e) that the invention is not useful; if) that the complete specification does not fully describe and ascertain the invention and the manner in which it is to be performed; (g) that the claims of the complete specification do not suffi­ ciently and clearly define the subject-matter for which pro­ tection is claimed; (h) that the complete specification does not disclose the best method of performing the invention known to the applicant at the time when the specification was lodged at the Patent Office; (i) that the application contains a material misrepresentation; (j) that the invention described or claimed in the complete specification is not the same as that described in the provi­ sional specification, and­ (i) in so far as it is not described in the provisional specification, was not new at the date when the complete specification was lodged at the Patent Office; or (ii) forms the subject of a pending application made in Zambia for a patent the effective date of which is prior to the date on which the complete specifica­ tion was lodged at the Patent Office; (k) in the case of a convention application, that the specifica­ tion describes or claims an invention other than that for which protection has been applied for in the convention country and that such other invention either­