The Grounds of Revocation: A Map of Section 64

1A patent granted may be revoked by proceedings before the high court on the grounds mentioned in s 64. A petition for revocation may be preferred by any person interested or by the Central Government before the high court. Revocation of a patent may also be sought for as a counter-claim in a suit for infringement of the patent before the high court. In an infringement suit, the defendant will be entitled to raise all the grounds by which a patent can be revoked under s 64 as a defence. (Patents Act 1970, s 107.)

2The Indian Patents and Designs Act 1911 provided for similar grounds of revocation. (Indian Patents and Designs Act 1911, s 26.) As the grounds in the Patents Act are essentially the same, recourse to decisions under the 1911 Act will be useful. Such has been the case in the United Kingdom where it has been held that when any doubt exists as to the meaning of expressions used in the sections of an earlier statute which sets out the grounds of invalidity of a patent, recourse may be had to earlier decisions and that any ambiguity must be resolved in favour of the meaning that is more consistent with the principles underlying them. (Bristol Myers Co (Johnson’s) Application [1974] FSR 43, p 64, (1975) RPC 127 (HL).)

3Section 64 details the grounds on which a patent can be revoked. The grounds in s 64 are comparable with the grounds of opposition under s 25, though the former are more elaborate. Section 107(1) states that the grounds of revocation contained in s 64 shall be available as a ground of defence in a suit for infringement.

4Section 32(1)(a) to (l) of the UK Patents Act 1949 detailed 12 grounds on which a patent could be revoked for invalidity. Under s 32(4) of the UK Patents Act 1949, the grounds of invalidity mentioned in s 32 could be raised as a defence in an infringement action. The grounds of revocation in s 32(1) of the UK Patents Act 1949 were strikingly similar to the grounds mentioned in s 64(1) of the Patents Act. Section 32(1) of the UK Patents Act 1949 read:

32. Revocation of patent by court.—(1) Subject to the provisions of this Act, a patent may, on the petition of any person interested, be revoked by the court on any of the following grounds, that is to say,—

(a) that the invention, so far as claimed in any claim of the complete specification, was claimed in a valid claim of earlier priority date contained in the complete specification of another patent granted in the United Kingdom; (b) that the patent was granted on the application of a person not entitled under the provisions of this Act to apply therefore; (c) that the patent was obtained in contravention of the rights of the petitioner or any person under or through whom he claims; (d) that the subject of any claim of the complete specification is not an invention within the meaning of this Act; (e) that the invention, so far as claimed in any claim of the complete specification, is not new having regard to what was known or used, before the priority date of the claim, in the United Kingdom; (f) that the invention, so far as claimed in any claim of the complete specification, is obvious and does not involve any inventive step having regard to what was known or used, before the priority date of claim, in the United Kingdom; (g) that the invention, so far as claimed in any claim of the complete specification, is not useful; (h) that the complete specification does not sufficiently and fairly describe the invention or the method by which it is to be performed, or does not disclose the best method of performing it which was known to the applicant for the patent and for which he was entitled to claim protection; (i) that the scope of any claim of the complete specification is not sufficiently and clearly defined or that any claim of the complete specification is not fairly based on the matter disclosed in the specification; (j) that the patent was obtained on a false suggestion or representation; (k) that the primary or intended use or exercise of the invention is contrary to law; (l) that the invention, so far as claimed in any claim of the complete specification, was secretly used in the United Kingdom, otherwise than as mentioned in sub-section (2) of this section, before the priority date of that claim;

5The similarity of s 32(1) of the UK Patents Act 1949 with the grounds of revocation under s 64(1) of the Patents Act makes it an ideal subject for a comparative analysis. Thus, the decisions rendered under s 32 of the UK Patents Act 1949 are discussed here in detail under the relevant headings. The provisions of the UK Patents Act 1949 were replaced by the UK Patents Act 1977. Section 72 of the UK Patents Act 1977 deals with the grounds for revocation of patent. Section 74 details the various proceedings in which these grounds may be raised. Significantly, the UK Patents Act has fewer grounds on which a patent can be revoked than the UK Patents Act 1949. The wording of s 72 of the UK Patents Act is not the same as that of s 32 of the UK Patents Act 1949. (See Mentor Corpn v Hollister Inc [1991] FSR 557, p 561.) “To this extent, due caution is required in relying on decisions under the UK Patents Act 1977.”

6As s 64(1) begins with the phrase ‘Subject to the provisions contained in this Act…’, the grounds in s 64(1) must be construed in the light of the other provisions of the Patents Act. Thus, the ground of revocation based on anticipation in cl (e) of s 64(1) will be subject to the provisions on anticipation contained in ch VI of Patents Act. This is all the more evident in the wording of s 34 which begins with the phrase ‘Notwithstanding anything contained in this Act…’. Revocation on the ground of anticipation must be understood to the extent stated in s 34." (See Justice N Rajagopala Ayyangar, ‘Report on the Revision of the Patent Laws’, September 1959, para 570.) “The grounds of revocation under s 64 are not subject to the grounds of opposition under s 25. Though the grounds of opposition and revocation appear to overlap, the Patents Act treats these grounds as distinct and separate. The grounds of revocation can be employed without prejudice to the grounds of opposition.

7Broadly, the grounds of revocation can be classified into two—external grounds of revocation and internal grounds of revocation. The grounds may also be classified differently based on the object at which these grounds are targeted. The grant and the revocation of a patent are closely interlinked by the common requirements which have to be satisfied in the case of grant and the absence of which has to be shown in the case of revocation. For the grant of a patent an invention has to satisfy the requirements imposed by the Patents Act. These requirements can broadly be classified under two heads—as external requirements of patentability and internal requirements of patentability—based on the stage in which they have to be met. (See Lionel Bently and Brad Sherman, Intellectual Property Law, 2000, p 457.) External requirements should be met before the decision to apply for a patent is made. Only when these requirements are satisfied, can a person approach the Patent Office with a patent application. The external requirements include subject matter, novelty and inventive step. Internal requirements are the requirements that have to be met in a patent application to the Patent Office. They pertain to matters that affect the manner in which a patent application is drafted. These requirements include sufficiency of disclosure, dependency of the claim on the matter disclosed (‘fair basis’) and scope of amendments.

8Similar to the external and internal requirements of patentability, the grounds of revocation of a patent may also be classified as external and internal grounds of revocation. (See Terrell on the Law of Patents, fifteenth edn, 2000, p 155.) The external grounds include grounds such as prior claiming, lack of novelty, lack of inventive step and prior use. The internal grounds of revocation include insufficiency of specification, lack of utility of invention, ambiguity of claims, lack of fair basis, non-disclosure of best method etc. As stated above, the grounds may be classified differently based on the objective of these grounds; a patent can be revoked for grounds which relate to the conduct of the patentee, the invention and its quality and description of invention. (See P Narayanan, Patent Law, fourth edn, ch 16.) (Patents Act 1970, ss 64(1)(b), 64(1)(c), 64(1)(j), 64(1)(m), 64(1)(n) and 64(1)(o).) (Ibid, ss 64(1)(a), 64(1)(d), 64(1)(e), 64(1)(f), 64(1)(g), 64(1)(k) and 64(1)(l).) (Ibid, ss 64(1)(h) and 64(1)(i).)

9In Cipla v F Hoffmann-La Roche (2015) the Division Bench held that “Lack of title not being a ground of revocation under Section 64 of the Patents Act, to press this point CIPLA ought to have insisted on settlement of a issue on lack of title” (para 172), that “the claim of Cipla qua the invalidity of the suit patent on the ground of lack of title cannot be decided in suit proceedings before this Court” (para 174), and that “lack of title is not a ground for revocation under Section 64 of the Patents Act.” (para 182)