Invalidity as a Defence

1On section 29 of the 1911 Act, Bishwanath Prasad Radhey Shyam v Hindustan Metal Industries (1978) recorded that “Sub-section (2) of the section provides that every ground on which a patent may be revoked under Section 26 shall be available by way of defence to a suit for infringement” (para 34), and held that “the grant and sealing of the patent, or the decision rendered by the Controller in the case of opposition, does not guarantee the validity of the patent” and that “this position, viz. the validity of a patent is not guaranteed by the grant, is now expressly provided in Section 13(4) of the Patents Act, 1970” (para 32).

2The defendant must state the manner, time and the place where the prior publication took place. In the case of prior use, the details about the person who has used the invention; the time during which and until which, such use took place and whether such use continued till the priority date of the patent; description along with drawings sufficient to identify such use; if the prior use involves an article, the place where it is and where it can be inspected. (See UK Civil Procedure Rules 1998, Part 63, paras 11.3 and 11.4)

3What is publicly known may be proved by oral evidence. The same applies to traditional knowledge, which expressly mentions ‘oral or otherwise’. Proof of oral disclosure should include the name of the persons who have such knowledge, place, time, circumstances and details about what was said. The defendant should specifically state what is known as the ‘common general knowledge’ in that particular art. Proof of ‘common general knowledge’ should disclose the documents which would be relied upon as being a part of the common general knowledge. (See Aluma Systems Inc v Hunnebeck GmbH [1982] FSR 239.)

4The defence under ss 3 and 4 of the Patents Act which details what are not inventions within the meaning of the Patents Act, have to be specifically pleaded.

5The defendant will have to give the details about the person whom it alleges to be the true and first inventor. (See Sylow-Hansen v June Hair Water Waver and Curler Co (1948) 65 RPC 421.) If the defendant alleges fraud, the particulars of the fraud will be necessary. (Code of Civil Procedure 1908, O 6, r 4. See Mulla’s Code of Civil Procedure, seventeenth edn, 2007, vol 2, p 292.)

6In alleging the ground of insufficiency, the defendant is not bound to show the plaintiff how to amend his specification. But if he alleges that there is a particular defect in it, which he intends to rely upon as rendering the patent void, he ought to say what that defect is. (See Crompton v Anglo-American Brush Electric Light Corpn [1887] LR 35 Ch D 283, p 286 (CA).) The objection of insufficiency rests not on the ground that one cannot carry the directions given in the specification, but that if one carries them the desired result is not achieved, that is to say, ‘If a skilled man follows the method directed in the specification, the results does not come out’. (See ‘Z’ Electric Lamp Manufacturing Co Ltd v Marples, Leach & Co Ltd (1909) 26 RPC 762 (CA).)

7In Farbwerke Hoechst v Unichem Laboratories (1968) the Bombay High Court stated that under section 29(2) “every ground on which a patent may be revoked under section 26 would be available by way of defence to a suit for infringement” (p 59), and that “the onus in regard to all objections to validity lies on the defendant” (p 64).

8In F Hoffmann-La Roche v Cipla (2009) the Division Bench held that “The mere registration of the patent does not guarantee its resistance to subsequent challenges. The challenge can be in the form of a counter-claim in a suit on the grounds set out in Section 64.” (para 52) It described “the very purpose of the legislature permitting a challenge by a Defendant to the validity of a patent in answer to an infringement suit, even if such Defendant had not earlier raised an opposition either at pre-grant or the post-grant stages” (para 65).

Defences to be pleaded specifically

9In Garware Wall Ropes v A.I. Chopra (2008) the Bombay High Court recorded that “Section 107 of the Patents Act provides for raising of defences in a suit for infringement and states that several grounds mentioned in Section 64 of the Act shall be available as grounds for defence in such suit.” The Court held that “It is not possible to appreciate the same on the grounds or defences mentioned in Section 64 of the Act in the absence of any pleadings or adequate pleadings of a party.” (para 12) It further held that “There is no explanation whatsoever by respondent No.1 as to why respondent No.1 did not oppose the grant/sealing of the patent or prayed for revocation thereof earlier to the suit and even in the suit by filing a counter claim. This conduct in my opinion, clearly shows that respondent No.1 was not serious in raising the defence as required by law.” (para 15)

10In Novartis v Cipla (2015) the Delhi High Court held at the interlocutory stage that “It is settled law that the allegation to challenge the suit patent must be specifically pleaded. The defendant must deliver the particulars of objection on every ground on which its validity is challenged and must include such particulars which will clearly define every issue.” (para 48) It found that “The defendant in order to show prior art has merely filed certain documents without explaining as to how they invalidate the suit patent. There is no required pleadings and argument advanced by the defendant.” (para 53)

11In AstraZeneca v Intas Pharmaceuticals (2020), the Delhi High Court held at the interlocutory stage that “Section 107 of the Act, expressly confers a right on the defendants to raise, in defence, in an infringement suit, all those grounds on which the patent can be revoked under Section 64 of the very same Act” and that the judgment in Bristol-Myers Squibb v J.D. Joshi “has not emasculated the right of the defendant, as conferred under the Act, to challenge the validity of the patent” (para 18.3).