Delhi High Court
Boehringer Ingelheim Pharma Gmbh And Co … vs The Controller Of Patents & Anr on 24 February, 2026
Author: C. Hari Shankar
Bench: C. Hari Shankar
$~
* IN THE HIGH COURT OF DELHI AT NEW DELHI
Reserved on: 26.11.2025
Pronounced on: 24.02.2026
+ LPA 129/2025, CM APPL. 10551/2025
BOEHRINGER INGELHEIM PHARMA
GMBH AND CO KG .....Appellant
Through: Dr. Abhishek Manu Singhvi
and Mr. Prashanto Chandra Sen, Sr. Advs.
with Dr Sanjay Kumar, Ms. Arpita
Sawhney, Ms. Pallavi Kiran, Mr. Arun
Kumar Jana, Ms. Pratiksha Varshney, Ms.
Shivangi Mayaramka, Ms. Atiksha Girdhar,
Mr. Siddhart Seem and Ms. Rashmi
Goswami, Advs.
versus
THE CONTROLLER OF PATENTS & ANR. .....Respondents
Through: Ms. Nidhi Raman, CGSC with
Mr. Arnav Mittal, GP with Mr. Mayank
Sansanwal, Adv. for R-1
Mr. G. Nataraj, Mr. Rahul Bhujbal, Mr.
Yash Raj and Mr. Jegadheesh R., Advs. for
R-2
Ms. Swathi Sukumar, Sr. Adv. (Amicus
Curiae)
CORAM:
HON'BLE MR. JUSTICE C. HARI SHANKAR
HON'BLE MR. JUSTICE OM PRAKASH SHUKLA
% JUDGMENT
24.02.2026
C. HARI SHANKAR, J.
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[Statutory provisions have been reproduced to the extent relevant.]
A. The lis
1. This appeal raises the following two pure questions of law:
(i) Whether a revocation petition, under Section 641 of the
Patents Act 1970, can be instituted or can survive after the
petitioner has pleaded invalidity of the patent, of which
revocation is being sought, as a defence under Section 107(1)2
of the Patents Act, in a suit instituted by the patentee against it?
(ii) Whether a revocation petition can be instituted or can
continue after the patent, of which revocation is being sought,
has expired?
2. These questions were raised by Boehringer Ingelheim Pharma
GMBH3, as Respondent 2 in CO (COMM IPD-PAT) 38/2022,
instituted by Macleods Pharmaceuticals Limited4 under Section 64 of
the Patents Act.
3. Both questions have been answered in the negative by a learned
1 64. Revocation of patents. –
(1) Subject to the provisions contained in this Act, a patent, whether granted before or after
the commencement of this Act, may, be revoked on a petition of any person interested or of the
Central Government or on a counter-claim in a suit for infringement of the patent by the High
Court] on any of the following grounds, that is to say,–
*****
2 107. Defences, etc. in suits for infringement. –
(1) In any suit for infringement of a patent, every ground on which it may be revoked under
Section 64 shall be available as a ground for defence.
3 “Boehringer” hereinafter
4 “Macleods” hereinafter
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Single Judge of this Court vide judgment dated 15 January 2025.
4. Aggrieved thereby, Boehringer is in appeal.
5. We have heard Dr. Abhishek Manu Singhvi and Mr Prashanto
Chandra Sen, learned Senior Counsel for the appellant and Mr.
Guruswamy Nataraj, learned Counsel for Macleods, at length.
Written submissions have also been filed.
B. Facts
6. Though the dispute is largely fact agnostic, we may briefly
advert to the factual backdrop in which the above issues arose.
7. Indian Patent (IN) 2433015 was granted to Boehringer on 5
October 2022, with a priority date of 21 August 2002, for the
pharmaceutical product Linagliptin. On 17 February 2022, CO
(COMM. IPD-PAT) 38/20226 was filed by Macleods under Section
64(1) of the Patents Act, seeking revocation of IN’301. Two days
thereafter, Boehringer filed COMS 3/2022 in the High Court of
Himachal Pradesh7 alleging that Macleods had infringed IN’301 and,
therefore, seeking injunctive and other reliefs against Macleods.
Macleods, in its written statement in the said suit, pleaded invalidity
of IN’301, thereby invoking Section 107(1) of the Patents Act.
8. Boehringer, in these circumstances, filed IA 7635/2024 and
5 “IN’301” hereinafter
6 “the revocation petition” hereinafter
7 “the Himachal suit” hereinafter
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46685/2024, seeking dismissal of the revocation petition on different
grounds. Both these applications stand dismissed by the impugned
judgment.
9. IA 7635/2024 pleaded that, as IN’301 had expired on 18 August
2023 by efflux of time, the revocation petition did not survive for
further consideration, as no revocation proceedings could either be
instituted or could continue once the patent of which revocation was
sought had expired.
10. IA 46685/2024 alleged that, having taken a Section 107 defence
in the Himachal suit, Macleods could not continue to maintain a
revocation petition.
C. Rival stands before the learned Single Judge
I. Boehringer's stand
11. With respect to Issue (i), i.e., the maintainability of the
revocation proceedings once a Section 107 defence had been taken by
Macleods in the Himachal suit, Boehringer submitted that, if the
revocation petitions were allowed to be proceeded with, it could result
in conflicting judgments in the suit and in the revocation petition
which were before two different High Courts, with the suit continuing
before the Himachal High Court and the revocation petition being
before this Court.
12. Boehringer further submitted that a finding of invalidity of
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IN’301, whether returned in the Himachal suit or in the revocation
petition, would be of equal effect, inasmuch as, in either case,
Boehringer would not be able to assert IN’301 thereafter. The finding
of invalidity, whether returned in the Himachal suit or in the
revocation petition, would operate in rem.
13. Keeping this position in mind, Boehringer contended that as the
suit proceedings were more comprehensive, where evidence would be
led and taken into consideration, and that, therefore, the aspect of
invalidity of IN’301 ought to be determined in the suit, rather than in
the revocation petition.
14. Apropos Issue (ii), Boehringer contended that a revocation
petition was maintainable only at the instance of a “person interested”.
Macleods could no longer be regarded as a “person interested” within
the meaning of Section 2(1)(t)8 of the Patents Act once IN’301 had
expired by efflux of time. For this proposition, Boehringer relied on
the judgment of a learned Single Judge of this Court in Dr. Reddys
Laboratories Ltd v. Controller of Patents9.
II. Macleod’s stand
15. Responding to Boehringer’s submissions, Macleods asserted,
before the learned Single Judge, that revocation proceedings and
proceedings relating to a Section 107 defence raised in a suit, were
qualitatively different, with different consequences. A decision on a
8 (t) “person interested” includes a person engaged in, or in promoting, research in the same field as that
to which the invention relates;
9 2022 SCC OnLine Del 1040
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revocation petition could only be taken by a High Court, whereas a
Section 107 defence in a suit could be adjudicated by a District Court.
Further, a defendant was not entitled while pleading a Section 107
defence, to seek revocation of the suit patent and could, at best, obtain
a declaration of invalidity and that the suit patent was liable to be
revoked. In this context, Macleods relied on Section 15110 of the
Patents Act.
16. It was further submitted that a revocation petition, if it
succeeded, would result in revocation of the patent in its entirety, as
though the patent had never existed on the register of patents. The
entire patent would stand removed from the register. As against this,
an invalidity defence under Section 107 could be raised qua individual
claims asserted in the suit and was not required to embrace the entire
suit patent.
17. With respect to Issue (ii), Macleods submitted that Section 64
was a standalone right, which could be asserted with or without the
suit and could therefore be raised even after the patent expired.
Similarly, expiry of a patent asserted in a suit did not bring the suit to
an end, as the cause of action, qua the claim for damages, survived.
Thus, the cause of action for filing a revocation petition would also
10 151. Transmission of orders of Courts to Controller. –
(1) Every order of the High Court on a petition for revocation, including orders granting
certificates of validity of any claim, shall be transmitted by the High Court to the Controller who
shall cause an entry thereof and reference thereto to be made in the register.
(2) Where in any suit for infringement of a patent or in any suit under Section 106 the
validity of any claim or a specification is contested and that claim is found by the Court to be valid
or not valid, as the case may be, the Court shall transmit a copy of its judgment and decree to the
Controller who shall on receipt thereof cause an entry in relation to such proceeding to be made in
the prescribed manner in a supplemental record.
(3) The provisions of sub-sections (1) and (2) shall also apply to the court to which appeals
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survive even after the suit patent had expired.
D. Findings of the learned Single Judge
18. As we have noted earlier, the learned Single Judge has, in the
impugned judgment, decided both the issues arising for consideration
in the negative.
19. Re: Issue (i)
19.1 With respect to Issue (i), the learned Single Judge has
proceeded on the following reasoning:
(i) The scope of a revocation petition under Section 64 and
of an invalidity defence under Section 107 of the Patents Act,
was different.
(ii) Section 64 of the Patents Act permitted a claim for
revocation to be raised either as a standalone petition under the
said provision or by way of a counter-claim in an infringement
suit. A High Court alone could adjudicate on such a claim. On
the other hand, Section 104 of the Patents Act also empowered
a district court to adjudicate on a Section 107 defence raised in
a patent infringement suit. However, if a counter-claim was
filed in a patent infringement suit, seeking revocation of the
patent, the suit, along with the counter-claim, was required to be
transferred to the High Court under Section 104 of the Patents
Act.
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(iii) Section 151 of the Patents Act was clearly illustrative of
the difference between a revocation petition under Section 64
and an invalidity defence under Section 107. A revocation
petition, if it succeeded, would, by operation of Section 151(1),
require the order to be transmitted to the Controller, who would
make a suitable entry in the Register of Patents, effacing, from
the Register, the patent, as if it had never existed. On the other
hand, an invalidity plea raised under Section 107, if it
succeeded, would be required to be transmitted to the Controller
of Patents under Section 151(2), who would make a suitable
entry in the supplemental record, on the basis of which the
defendant in the suit could take separate steps under Section
71(1)11 of the Patents Act for rectification of the Register. A
finding of invalidity, which would follow from a successful
Section 107 challenge would not, therefore, result in effacing of
the suit patent from the Register of Patents.
(iv) This was also clear from the prayers made by Macleods
in the Himachal Suit and in the revocation petition. In the
Himachal Suit, Macleods prayed for a declaration of invalidity
of IN’301, which would render the suit patent liable to be
revoked and removed from the Register of Patents. As against
this, in the revocation petition, Macleods sought removal of
11 71. Rectification of register by High Court. –
(1) The High Court may, on the application of any person aggrieved–
(a) by the absence or omission from the register of any entry; or
(b) by any entry made in the register without sufficient cause; or
(c) by any entry wrongly remaining on the register; or
(d) by any error or defect in any entry in the register,
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IN’301 from the Register of Patents.
(v) Section 58(1)12 of the Patents Act empowered the High
Court, even if it felt that the patent of which revocation was
being sought, was invalid, to allow the patentee to amend the
complete specifications of the patent to save it from
annihilation, instead of revoking the patent. As against this,
while dealing with an invalidity defence under Section 107, the
Court seized of the suit could not direct amendment of the suit
patent or of the claims therein. This, too, served as a point of
distinction between a revocation petition and an invalidity
defence in a suit.
(vi) A finding in a suit, including a finding on an invalidity
plea raised under Section 107, operated inter partes and in
personam. Section 11413 of the Patents Act empowered the
court, even if some of the claims in the suit patent were declared
invalid, to grant reliefs on the other claims. On the other hand, if
a patent was revoked under Section 64, the decision would
12 58. Amendment of specification before High Court. –
(1) In any proceeding before the High Court for the revocation of a patent, the High Court
may, subject to the provisions contained in Section 59, allow the patentee to amend his complete
specification in such manner and subject to such terms as to costs, advertisement or otherwise, as
the High Court may think fit, and if, in any proceedings for revocation, the the High Court decides
that the patent is invalid, it may allow the specification to be amended under this section instead of
revoking the patent.
13 114. Relief for infringement of partially valid specification. –
(1) If in proceedings for infringement of a patent it is found that any claim of the
specification, being a claim in respect of which infringement is alleged, is valid, but that any other
claim is invalid, the court may grant relief in respect of any valid claim which is infringed:
Provided that the court shall not grant relief except by way of injunction save in the
circumstances mentioned in sub-section (2).
(2) Where the plaintiff proves that the invalid claim was framed in good faith and with
reasonable skill and knowledge, the court shall grant relief in respect of any valid claim which is
infringed subject to the discretion of the court as to costs and as to the date from which damages or
an account of profits should be reckoned, and in exercising such discretion the court may take into
consideration the conduct of the parties in inserting such invalid claims in the specification or
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operate in rem, and the patentee would not, thereafter, be able to
assert any of the claims in the patent against any party.
19.2 Predicated on the above reasoning, the learned Single Judge
found that taking of a Section 107 invalidity defence would not inhibit
the defendant in a suit from pursuing revocation proceedings under
Section 64 of the Patents Act.
19.3 The learned Single Judge did not adjudicate on the plea of
possibility of contrasting decisions in the Himachal Suit and in the
revocation petition, on the ground that the Supreme Court was seized
of this aspect in transfer proceedings pending before it, whereby it had
been prayed that the Himachal Suit be transferred to this Court.
20. Re: Issue (ii)
20.1 With respect to Issue (ii), the learned Single Judge reasoned as
under:
(i) A revocation petition was maintainable at the instance of
a “person interested”. The expression “person interested” was
defined in Section 2(1)(t) of the Patents Act. Inasmuch as
Macleods was interested in the manufacture and sale of the
products patented under IN’301, and was also a defendant in the
Himachal Suit instituted by Boehringer against it, Macleods was
“a person interested” within the meaning of Section 2(1)(t), and,
therefore, also Section 64 of the Patents Act.
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(ii) The expiry of a suit patent did not bring a suit to an end,
as the cause of action in the suit continue to survive qua the
claim for damages. Damages had specifically been claimed by
Boehringer in the Himachal Suit against Macleods. This claim
would survive even after the expiry of IN’301. Mutatis
mutandis, the revocation petition would also survive.
(iii) If Macleods were to succeed in the revocation
proceedings and IN’301 were to be revoked, Boehringer’s
Himachal Suit would be liable to be dismissed. This also
indicated that a valid cause of action survived in favour of
Macleods, which it could continue to contest even after IN’301
had expired by afflux of time.
20.2 The expiry of the suit patent, therefore, it was held, would not
have any effect on the revocation proceedings.
21. Aggrieved by the aforesaid order, Boehringer is, as we have
already noted, in appeal before us.
E. Rival contentions of learned Counsel before this Court
I. Submissions of Dr. Abhishek Singhvi
22. Appearing for Boehringer, Dr. Singhvi submits that the very
concept of revocation of a patent ipso facto presumed that the patent
was alive. There could be no question of revoking a patent which had
already expired.
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23. Dr. Singhvi further submits that the maintainability of a
revocation petition, after the patent sought to be revoked had expired,
could not be gauged on the basis of the consequence which would
follow if the petition were allowed, or otherwise. That apart, he
submits that a patent merely created a monopoly in the rights which it
conferred. While it was alive, the monopoly was with the patent
holder and, after it expired, the patented invention was available to the
whole world to exploit. The only consequence of a revocation petition
being allowed was, therefore, wiping out of this monopoly. Dr.
Singhvi submits that there is no decision, or authority, to the effect
that the revocation of a patent would date back to its grant.
24. The reliance, by the learned Single Judge, on Section 151 of the
Patents Act, submits Dr. Singhvi, is misconceived. Transmission of
the order of revocation to the Controller of Patents, after the patent has
expired by efflux of time, is akin to flogging a dead horse. He relies
on the judgment of the Division Bench of this Court in Ajay
Industrial Corporation v. Shiro Kanao of Ibaraki City14 and on the
decision of the High Court of Calcutta in Star Textile Engineering
Works Ltd v. James Mackie Holding Ltd15.
25. On the maintainability of the revocation petition after Macleods
had pleaded invalidity of IN’301 in the Himachal Suit, Dr. Singhvi
relies on the following passage from the decision in Aloys Wobben v.
14 AIR 1983 Del 496
15 1977 SCC OnLine Cal 280
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Yogesh Mehra16:
“26. In cases where the “infringement suit(s)” was/were filed by
the appellant herein (as plaintiff in the “infringement suit”), before
the “revocation petition(s)” was/were filed by the respondents (as
defendants in the “infringement suit”), the respondents had the
right to file “counterclaim(s)” to seek revocation of the patent
under the strength and authority emerging from Section 64(1) of
the Patents Act. Having once filed a “counterclaim” in response to
the “infringement suit(s)” on the same analogy as has been
recorded above, it would not be open to the respondents herein (the
defendants in the “infringement suits”) to file “revocation
petition(s)”, as they would likewise be barred by the rule of res
judicata. As such, “revocation petitions” filed later in point of time
than the institution of the “infringement suit”, would be
unsustainable in law. In such cases, the prayer for revocation of the
patent shall be adjudicated while disposing of the “counterclaim”
filed by the respondents. Therefore, in the above situation, while
the “counterclaim” will have to be permitted to be pursued, the
“revocation petition” cannot be permitted to be continued.”
In view of the law declared in the above passage, Dr. Singhvi submits
that, once a plaintiff files a patent infringement suit, the only options
with the defendant is to raise an invalidity defence under Section 107
of the Act or prefer a counter-claim if the defendant seeks revocation
of the patent. He cannot continue to maintain a revocation petition
under Section 64.
26. Adverting to the proceedings in the Himachal suit, Dr. Singhvi
submits that the suit was filed on 19 February 2022; the revocation
petition was filed by Macleods on the very next day, i.e. 20 February
2022; ad interim injunction in favour of Boehringer was granted in the
suit on 25 February 2022, which was made absolute on 21 April 2022,
and the appeal thereagainst, preferred by Macleods, was dismissed by
the High Court on 12 March 2024. In these circumstances, Dr. Singhvi
16 (2014) 15 SCC 360
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submits that Macleods would, if it so chooses, have to prefer a
counter-claim in the Himachal suit, and allowing it to pursue the
revocation petition would merely result in multiplicity of litigation.
27. Both issues, therefore, submits Dr. Singhvi, have been wrongly
decided by the learned Single Judge.
II. Submissions of Mr. Prashanto Chandra Sen
28. Supplementing the submissions of Dr. Singhvi, Mr. Prashanto
Chandra Sen submits that a Section 107 defence is essentially in the
nature of a counter-claim. He relies, for the purpose, on the judgment
of a learned Single Judge of this Court in Unilin Beheer B.V. v. Balaji
Action Buildwell17. He further cites para 19 of Aloys Wobben and
paras 26 and 28 of Ramesh Chand Ardawatiya v. Anil Panjwani18.
29. Mr. Sen further placed reliance on Section 2(o)19, read with
Section 53(4)20, of the Patents Act.
III. Submissions of Mr. Guruswamy Nataraj
30. Mr. Guruswamy Nataraj commences his submissions by
pointing out that Section 64 uses the expression “a patent”, and not a
“patent in force”. Had the legislature desired to use the latter
17 (2018) 76 PTC 194
18 (2003) 7 SCC 350
19 (o) “patented article” and “patented process” mean respectively an article or process in respect of
which a patent is in force;
20 (4) Notwithstanding anything contained in any other law for the time being in force, on cessation of the
patent right due to non-payment of renewal fee or on expiry of the term of patent, the subject-matter covered
by the said patent shall not be entitled to any protection.
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expression, submits Mr. Nataraj, it would have done so. Court, he
submits, cannot supply casus omissus.
31. Mr. Nataraj further submits that the conflation between a
Section 107 defence, a counter-claim, and a revocation proceeding,
which learned Senior Counsel for the appellant attempts, is completely
unsustainable in law. He submits that a revocation proceeding under
Section 64, and a counter-claim, are paths to revocation. A Section
107 defence, on the other hand, even if it succeeds, does not result in
revocation of the patent. The effect of revocation, he submits, is
effacement of the patent ab initio, as if it were never granted. The
legal effect, however, would persist, and a plaintiff may still be
entitled to damages.
32. In the present case, submits Mr. Nataraj, as Boehringer is, in its
Himachal suit against Macleods, also pressing for account of profits,
Macleods cannot be disentitled from prosecuting its revocation
petition.
33. The right to seek revocation of a patent under Section 64,
submits Mr Nataraj, is a standalone remedy, which can be exercised at
any time. The Patents Act does not engraft any restriction in this
regard. A prayer seeking revocation of a patent can, therefore, be
preferred either as a counter-claim or as a standalone revocation
petition, whether before or after the expiry of the patent.
34. Mr. Nataraj seeks to point out that sub-sections (1) and (2) of
Section 151 also emphasize the distinction between revocation and a
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Section 107 defence. Success in a revocation proceeding would
require the decision to be transmitted to the Controller of Patents, who
would make an entry thereof in the Register of Patents. On the other
hand, success in a Section 107 invalidity defence would only obligate
the Court to transmit a copy of its decision to the Controller who
would make an entry in that regard in a supplemental record. The
result of success in a Section 107 invalidity defence would, therefore,
at best be declaratory, and would not revoke the patent itself. The
entry of the patent in the Register of Patents would, therefore,
continue to remain, inviolate. Mr. Nataraj has also relied, in this
context, on paras 284 to 291 of the Ayyangar Committee Report
which preceded the amendment of the Patents Act, which read thus:
“284. The proceedings in relation to patents yet to be considered
are: (1) Suits for infringement (clause 58 of the Bill). (2) Suits for a
declaration as to non-infringement (clause 57). (3) Suits
complaining of groundless threats of infringement proceedings
(clause 66).
285. Section 29 of the Indian Patents & Designs Act, 1911,
enables a patentee to institute a suit in a District Court having
jurisdiction to try the suit against any person who has infringed his
right with a proviso that where the defendant counter-claims for
revocation the suit along with the counter-claim should stand
transferred to the High Court for decision. Clause 58 of the Bill
reproduces in substance the above provisions in section 29 of the
Act.
*****
287. The existence of this defence raises questions as to the
manner in which possible differences between different Courts as
to the validity or invalidity of the claims of a patent should be
resolved. To make my meaning clear I would add this. A patent
might be infringed by more persons than one and if these infringers
reside in or carry on business or commit the act of infringement in
different areas of the country, the several suits for infringement
would have to be filed in District Courts in different States. The
defence regarding the invalidity of the patent might be raised in
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more than one Court and these Courts might decide differently the
point about the validity of the patent. In the United Kingdom this
problem of conflicting decisions does not arise because all suits for
infringement have to be filed in the High Court.
288. In the case of Trade Marks where conflicts of decisions of
this type also arise, I recommended the procedure of having the
suits for infringement in which the validity of the registration of the
mark was raised, stayed and requiring the person raising the point
of invalidity of the registration to move the competent High Court
for the rectification of the Register. I do not think it is necessary to
adopt such a procedure in the case of suits for infringement of
patents. The number of such suits would be so few that such a
complicated procedure is not called for.
289. In its place I would recommend the following. A suit for
infringement may be filed in any court not inferior to a District
Court which has territorial jurisdiction under the Civil Procedure
Code to entertain it. All defences including those based on the
invalidity of the patent would be gone into by that Court and by the
appellate Courts if appeals were filed. But any finding by the Court
that the patent or any claim therein was invalid would not have any
effect on the patent as such and would not lead to the revocation of
the patent. In other words, the decision in the suit would be merely
one inter-partes operating between them by way of res judicata and
not one in technical phraseology “in rem” affecting the patent
itself.
Revocation proceedings only before High Court having
jurisdiction
290. If any person interested were desirous of obtaining an
adjudication which would, if successful, have an effect on the
patent itself and beyond the immediate parties to that proceeding,
he should file a petition for revocation of the patent, and the forum
for this proceeding would be exclusively the High Court having
territorial jurisdiction over the office where the patent is registered.
If the petition succeeds, and the patent is held invalid, then subject
to the result of any appeal preferred against such a decision, the
patent would be revoked and an entry to that effect would be made
in the Register of Patents. It is needless to add that where the Court
dismisses the petition for revocation, there would be no legal bar
against other persons interested in initiating fresh proceedings for
revocation, though, save in exceptional circumstances, the chances
of such a petition succeeding, particularly since the later
proceeding also would be in the same High Court, would be very
remote.
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“Supplemental Record” for entries of decisions as to validity in
infringement
291. I have referred to the fact that when a petition for
revocation succeeds, appropriate entries would be made in the
Register of Patents. It is now necessary to mention what should
happen in cases where a Court pronounces against the validity of a
patent in a suit for Infringement. The decision of the trial court
might be taken up in in appeal to a High Court, or the sunt itself
might be tried in a High Court, and it is therefore proper that some
record should be made of this finding for the information of other
persons interested in the patented invention. I would recommend
the opening of a “supplemental record” and entries being made in
such record of the result of proceedings, which, though of
importance in relation to the validity of a patent grant, do not
legally affect the patent itself. The patent may be the subject of
sale, or of licensing and it would be of the utmost importance to the
prospective purchase or licensee to be informed of what any court
has pronounced regarding the validity or invalidity of the claims in
a patent.”
35. Mr. Nataraj submits that the expiry of a patent does not efface
the right of the patentee to claim damages, under Section 10821 of the
Patents Act, for infringement which took place during the life of the
patent. This right also stands recognized by Section 4822 of the Patents
Act.
36. Mr. Nataraj has also placed reliance on paras 25 to 27 of the
judgment of the Supreme Court in Aloys Wobben and the decision of
21 108. Reliefs in suits for infringement. –
(1) The reliefs which a court may grant in any suit for infringement include an injunction
(subject to such terms, if any, as the court thinks fit) and, at the option of the plaintiff, either
damages or an account of profits.
(2) The court may also order that the goods which are found to be infringing and materials
and implements, the predominant use of which is in the creation of infringing goods shall be seized,
forfeited or destroyed, as the court deems fit under the circumstances of the case without payment
of any compensation.
22 48. Rights of patentees. – Subject to the other provisions contained in this Act and the conditions
specified in Section 47, a patent granted under this Act shall confer upon the patentee–
(a) where the subject-matter of the patent is a product, the exclusive right to prevent third
parties, who do not have his consent, from the act of making, using, offering for sale, selling or
importing for those purposes that product in India;
(b) where the subject-matter of the patent is a process, the exclusive right to prevent third
parties, who do not have his consent, from the act of using that process, and from the act of using,
offering for sale, selling or importing for those purposes the product obtained directly by that
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a Division Bench of this Court in Ajay Industrial Corporation.
37. Mr. Nataraj points out that removal of a patent from the
Register of Patents is governed by a separate provision, viz., Section
7123.
38. Mr. Nataraj further relies on the definition of “patent” in the
Patents Act, which means “a patent for any invention granted under
this Act”. Mr. Nataraj emphasizes the word “granted”. He submits
that, once granted, a patent remains a patent till it is revoked. The
word “patent” in Section 64, he submits, has to be understood in the
light of the definition of “patent” in the Patents Act. It cannot be read
as a patent in force. He also relies, in this context, on the definition of
“revoke” in Black’s Law Dictionary Revised Fourth Edition, which
reads “to annul or make void by recalling or taking back, cancel,
rescind, repeal, reverse” and in P. Ramanatha Aiyar’s Advanced Law
Lexicon 7th Edn, which reads “an act of recalling or calling back, the
act by which one having the right annuls something previously done”.
39. The reliance, by Mr. Sen, on Section 53(4) of the Patents Act is,
according to Mr. Nataraj, misplaced. Section 53(4) only impacts the
patentee’s right to sue, and has no effect on Macleod’s right to
maintain the revocation petition.
23 71. Rectification of register by High Court. –
(1) The High Court may, on the application of any person aggrieved–
(a) by the absence or omission from the register of any entry; or
(b) by any entry made in the register without sufficient cause; or
(c) by any entry wrongly remaining on the register; or
(d) by any error or defect in any entry in the register,
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40. Mr. Nataraj submits that, before any infringement suit is filed, a
revocation petition under Section 64 would in any case be
maintainable. After an infringement suit has been filed, the defendant
can raise a Section 107 invalidity defence and seek revocation of the
patent either via a revocation petition under Section 64 or by way of a
counter-claim, though a revocation petition and a counter-claim
cannot simultaneously be maintained, as held in Aloys Wobben.
41. Adverting to Aloys Wobben, Mr. Nataraj submits that the
decision is being cited entirely out of context, and that para 26 thereof,
which Dr. Singhvi and Mr. Sen rely on, is not even its ratio decidendi.
He submits that Aloys Wobben involved an instance of a revocation
petition and counter-claim having been filed before two different fora;
the former before the IPAB and the latter before the High Court. Even
after the IPAB had invalidated certain patents, the revocation
petitioner continued to file counter-claims, seeking revocation of the
same patents, in infringement suit. It was in these circumstances that
the Supreme Court held that the counter-claim could not be pursued.
Macleods, on the other hand, had only raised a Section 107 invalidity
defence and had not preferred any counter-claim.
42. Mr. Nataraj submits, if the arguments of the appellant were to
be accepted, a counter-claim would also perish with the expiry of the
patent. He seeks to distinguish Ramesh Chand Ardawatiya on the
ground that the issue in controversy in the present case is governed by
Section 64 and its interpretation. In Unilin, he points out that this
Court granted liberty to file a revocation petition, which means that
the patent remains on the register even after its expiry.
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43. Finally, Mr. Nataraj submits that, even after an invalidity
defence succeeds, the patentee-plaintiff can seek to amend the invalid
claims under Section 58 or 59 of the Patents Act, or seek a validity
certificate under Section 113. Thereafter, the claim would again be
open to assertion. As against this, a revocation action, if it succeeds,
eviscerates the patent entirely, and it cannot be revived in any manner
and to any extent.
IV. Submissions of Ms. Swathi Sukumar, learned amicus curiae
44. Ms. Swathi Sumar, learned Senior Counsel, who ably assisted
us at our request as amicus, submitted that the Patents Act provides
for a challenge to be laid to the validity of a patent, and for the
patentee to repel the challenge, in a pre-grant opposition, post-grant
opposition, revocation, a Section 107 invalidity defence, a declaration
of non-infringement as well as compulsory licensing. Each, she
submits, is distinct and different. She draws attention to paras 37 and
44 of the Ayyangar Committee Report, which read:
“37. In the present decade under the impact of the national plans
that have been formulated for the economic uplift of the country
and the raising of the standard of living of its people, the
conservation of foreign exchange is a matter of prime importance.
In the context of this need, it would be seen that any increase in the
price of the patented products imported into the country must to
that extent be a disadvantage to the nation’s economy. This apart,
there is also the factor that by reason of these patents, our country
is deprived of the benefits of importing from that country, payment
in whose currency would be the least burdensome to India. Due to
the existence of the grants, this country has no choice as regards
the currency to be paid for the importation because this depends
not on our choice but on the location of the patentee’s manufactory
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or the country from which the patentee chooses to import for sale
in India.
*****
What changes are necessary in the Indian law
44. The precise provisions of the Patent law, however, have to
be designed, with special reference to the economic conditions of
the country, the state of its scientific and technological advance, its
future needs and other relevant factors and so as to minimise if not
to eliminate the abuses to which a system of patent monopoly is
capable of being put.”
45. Ms. Sukumar endorses Mr. Nataraj’s submission that, as an
infringement suit, qua the claim for damages therein, would not lapse
even after expiry of the patent, the issue of revocation continues to
retain significance. In any event, she submits that Section 64 uses the
expression “person interested”. It is not, therefore, open ended, and
can be maintained only by such a person. So long as the applicant
seeking revocation of the patent remains a “person interested”, Ms.
Sukumar submits that the revocation action would be maintainable.
46. To support her submissions, Ms. Sukumar places reliance on
para 21 of Aloys Wobben, para 15 of Girdhari Lal Gupta v. K. Gian
Chand Jain24 and various paragraphs from Ajay Industrial
Corporation. She also relies on Section 108 of the Patents Act, which
provides for the reliefs available in a case of infringement.
V. Submissions of Mr. Prashanto Chandra Sen in rejoinder
47. Arguing in rejoinder, Mr. Prashanto Chandra Sen submits that
the concept of a “person interested” is dynamic, and that no person
24 AIR 1978 Del 146
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can continue to be interested in a revocation proceeding once the
patent of which revocation is sought has itself expired by efflux of
time. Once the corpus of the interest does not subsist, he submits, the
interest must also perish. He relies on paras 10 to 12 of the decision
of a learned Single Judge of this Court in Dr Reddys Laboratories.
48. Mr. Sen responds to Mr. Nataraj’s emphasis on the word
“granted” in the definition of “patent” as contained in Section 2(o) of
the Patents Act by submitting that the grant would subsist only so long
as the patent is alive. The grant is, therefore, limited; not unlimited.
He relies, for this purpose, on para 17 of Bishwanath Prasad Radhey
Shyam v. Hindustan Metal Industries25, which specifically says so.
49. Mr. Sen concludes his submissions by referring to para 10 of
Ajay Industrial Corporation and para 9 of the judgment of the
Supreme Court in Ibrahim Bachu Bafan v. State of Gujarat26.
F. Analysis
I. Section 64 - Revocation acts retrospectively - Definition of
"patent" - "Person interested"
50. Section 64 states that a patent may be revoked on a petition of
any person interested or of the Central Government, or on a counter-
claim in an infringement suit. The pivotal words are, to our mind,
“patent”, “revoked”, “person interested” and “or on a counter-claim”.
25 (1979) 2 SCC 511
26 (1985) 2 SCC 24
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51. We deem it appropriate, first, to address the expression
“revoked”. A major point of controversy, among learned Counsel, is
whether “revocation” of a patent under Section 64 would invalidate
the very grant, i.e., whether it would operate retrospectively from the
date of grant, or prospectively from the date of revocation. Mr. Nataraj
and Ms. Sukumar assert the former, whereas Dr. Singhvi and Mr. Sen
submit that there is no legal basis for the proposition that revocation
would date back.
52. Unfortunately, the Patents Act does not directly address this
issue, or throw any direct light thereon. However, it is not entirely
silent on the issue, and an answer to the poser, to our mind, is
available even in Section 64 itself.
53. Having addressed ourselves to this issue, we are of the view that
the submission of Mr. Nataraj and Ms. Sukumar deserves to be
accepted. We say so for various reasons.
54. Firstly, Section 64 states that a patent may “be revoked on a
petition of any person interested or the Central Government or on a
counter-claim in a suit for infringement of the patent by the High
Court”. A petition for revocation and a counter-claim in an
infringement suit which already stands instituted, are therefore, at par,
as both are governed by Section 64. Section 64 clearly envisages
success in both to result in the same legal consequence, i.e. revocation
of the patent. This is expressed from the words of the provision. It
clearly states that a granted patent may be revoked either by a
revocation petition or by a counter-claim in an instituted suit.
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55. As Section 64 envisages revocation of a granted patent to be
permissible as much by a revocation petition as by a counter-claim in
an instituted suit, the consequences of either action have to be the
same. A counter-claim in an instituted suit would invariably seek a
declaration that the grant of the patent is itself invalid as, else, there
would be no advantage in filing any such counter-claim at all. The
assertion of infringement in an instituted suit, is also the claim for
damages on the basis of such infringement, would invariably be prior
to the date of institution of the suit, after the patent has been granted.
Any counter-claim, filed to question the claim of the plaintiff would,
therefore, invariably have to seek a declaration of invalidity of the suit
patent ab initio.
56. Inasmuch as Section 64 envisages the consequence of
revocation petition and of a counter-claim in an instituted suit being
the same, i.e. revocation of the patent, the revocation would, in either
case, invalidate the very grant of the patent and would date back to the
date of grant. Hence, it would run counter to the intent of the
legislature in envisaging a revocation petition and a counter-claim in
an infringement suit as both being avenues for obtaining revocation of
the patent under Section 64.
57. As a defendant in an infringement suit, therefore, apart from
raising a Section 107 invalidity defence, the defendant can seek
revocation of the patent either by a counter-claim seeking a
declaration to that effect or by way of a revocation petition, but not
both. Both would lie under Section 64.
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58. Secondly, without proceeding ground-by-ground, a glance at
the grounds on which revocation of a patent may be sought under
Section 64, with the preceding provisions in the Patents Act governing
grant of a patent, reveal that the grounds on which revocation can be
sought, if found to be justified, but invariably indicate that the very
grant of the patent was invalid. To wit, a patent cannot be granted if
the claim in the patent has been claimed in an earlier granted patent of
earlier priority date; or if the applicant is not entitled to apply for the
patent; or if the claim does not relate to any invention within the
meaning of the Patents Act; or if the invention is obvious from prior
art; or if the invention lacks novelty and any inventive step; or if the
invention is not useful; or if the complete specification in the
application does not sufficiently and fairly describe the invention and
the method by which it is to be performed; or if the scope of the claim
is not clearly and sufficiently defined in the complete specification; or
if there is any misrepresentation or falsity in the application; or if the
subject of the claim is not patent a under the Patents Act; or if the
invention was secretly used in India before the priority date of the
claim; or if information as required by Section 8 of the Patents Act is
not disclosed; or if any direction for secrecy passed under Section 35
is contravened by the applicant; or if leave to amend the complete
specification was obtained by fraud; or if the complete specification
does not correctly disclose the source or geographical origin of
biological material used in the invention. If a granted patent is found
to be invalid on any of these grounds, it would mean that the very
grant of the patent was invalid. Even for this reason, therefore, the
revocation of a granted patent under Section 64 has to date back to the
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date when the patent was granted.
59. Thirdly, this view of ours is also supported by judicial authority,
albeit largely from foreign jurisdictions. The only judgment from an
Indian court which seems to speak on the issue is by a learned Single
Judge of the High Court of Calcutta in Star Textile Engineering
Works which, in para 12, merely records the submission of learned
Counsel before the Court, premised on the decision in North Eastern
Marine Engineering Co. Ltd v. Leeds Forge Co. Ltd27, that “though
the patent has expired there is no bar for the Court revoking the
same”. It does not appear, however, that the High Court independently
addressed itself to the correctness of this proposition.
60. We are, however, supported, in our view, by the judgment of
the UK Supreme Court in Virgin Atlantic Airways Ltd v. Zodiac
Seats UK Ltd28. Before adverting to the said decision, however, it is
necessary to refer to the provisions of the patent law governing UK at
the time when the decision was rendered.
61. Virgin Atlantic Airways dealt with “a “European Patent
(UK)”29, i.e. one which is granted for the United Kingdom or for states
including the United Kingdom”.30 Para 4 of the decision clearly states
that, as per Section 77(1) of the UK Patents Act, 197731, a European
Patent (UK) “is to be treated as if it were a patent granted under the
Act”. European Patents (UK) and UK Patents, thereby, stand equated
27 23 RPC 96
28 [2009] EWCA Civ 1062
29 “the UK Patent” hereinafter
30 Refer para 4 of Virgin Atlantic
31 “the UKPA” hereinafter
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under the UK Patents Act. In this backdrop, Article 68 of the
European Patent Convention32 is significant. It reads thus:
“Effect of revocation or limitation of the European patent
The European patent application and the resulting European patent
shall be deemed not to have had, from the outset, the effects
specified in articles 64 and 67, to the extent that the patent has
been revoked or limited in opposition, limitation or revocation
proceedings.”
Thus, revocation of a European patent operates, under the EPC, ab
initio, i.e. the patent stands revoked from the date of grant.
62. Section 72 of the UKPA deals with revocation of UK patents.
Though Section 72 does not state that revocation would operate
retrospectively from the date of grant of the patent, Section 130(7)33
of the UKPA provides that Section 72(1) and (2) of the UKPA would
have, as nearly as practicable, the same effects in the UK as the
corresponding provisions of the EPC. This would, therefore, make the
stipulation, regarding retrospective revocation of a European patent
under the EPC, provided in Article 68 of the EPC, mutatis mutandis
applicable to revocation of a UK patent under the UKPA.
32 “the EPC” hereinafter
33 130. Interpretation.
*****
(7) Whereas by a resolution made on the signature of the Community Patent Convention the
governments of the member states of the European Economic Community resolved to adjust their
laws relating to patents so as (among other things) to bring those laws into conformity with the
corresponding provisions of the European Patent Convention, the Community Patent Convention
and the Patent Co-operation Treaty, it is hereby declared that the following provisions of this Act,
that is to say, sections 1(1) to (4), 2 to 6, 14(3), (5) and (6), 37(5), 54, 60, 69, 72(1) and (2), 74(4),
82, 83, . . . 100 and 125, are so framed as to have, as nearly as practicable, the same effects in the
United Kingdom as the corresponding provisions of the European Patent Convention, the
Community Patent Convention and the Patent Co-operation Treaty have in the territories to which
those Conventions apply.
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63. In this backdrop, the following passages from Virgin Atlantic
Airways makes for instructive reading:
(per Lord Sumption)
“28. How then did the Court of Appeal come to a different
conclusion? The answer is that they followed a line of cases
culminating in the decision of the Court of Appeal in Unilin
Beheer BV v Berry Floor NV [2007] FSR 635, which had held that
a patentee whose patent has been held to be valid is entitled to
claim damages for its infringement without regard to a subsequent
revocation of the patent. This has been held to be so, even though
it has always been the law in England (as it is under the European
Patent Convention) that the revocation of a patent for invalidity
relates back to the date of grant: see, currently, section 75(3) of the
Patents Act 1977.
*****
32. …..The revocation of the patent was an act in rem which
determined the status of the patent as against the world. It had been
revoked by the authority which had granted it and must be treated
as never having existed. Although the patent had been revoked on
the ground of invalidity, the issue which the defendant wished to
raise on the enquiry was not invalidity but revocation. The
revocation would be decisive regardless of the ground on which it
was ordered.”
(per Lord Neuberger)
“49. The essential point is that, although the decision to revoke
the patent was indeed made in proceedings involving different
parties, the effect of the Patents Act 1977 (and its statutory
predecessors) (“the Patents Act“) and the European Patent
Convention (“the EPC”) whose relevant provisions are set out in
paras 3-7 of Lord Sumption’s judgment, was that the revocation
did not just have effect between those parties. The revocation of
the patent deprived the patentee of the rights which the patent had
bestowed on him as against the world; furthermore, it did so
retrospectively. In other words, the effect of the revocation was
that everyone was entitled to conduct their affairs as if the patent
had never existed.
*****
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51. In Poulton34 and the cases which followed it, the Court of
Appeal failed to focus on the point that the effect of the Patents
Act was that the revocation meant that, as against the world, the
patentee had never had a valid patent.
*****
58. The policy of the Patents Act is that valid patents are
enforceable against the world, even if an infringer is honestly and
reasonably unaware of the existence of the patent. Equally, if a
patent is revoked (or amended), the policy is that the revocation (or
amendment) takes effect retrospectively, and that this can be relied
on by the world. I find it hard to see why someone who has failed
in an attack on the patent should not be entitled, like anyone else,
to rely on the points that the patent has been revoked (or amended),
and that the revocation (or amendment) is retrospective in its
effect, whether in legal proceedings or in another context.
*****
61. So far as the interests of patentees are concerned, it is
inherent in the grant of a patent under the Patents Act that,
however often its validity may be unsuccessfully challenged in
earlier litigation, it may none the less be revoked (or amended),
and with retrospective effect, at some point by a court or by the
EPO.”
64. In view of the fact that a conjoint and juxtaposed reading of the
provisions of the UKPA, cited supra, reveals the statutory position in
the UK, with respect to revocation of patents, to be similar to that
which exists under the Patents Act, we may usefully rely on the
aforesaid decision of the UK Supreme Court in Virgin Atlantic
Airways to support our conclusion that revocation acts in rem and
retrospectively from the date of grant.
65. Patent rights are often trans-national in nature. It is rarely that
patents are restricted to a country alone, and most patents have their
genesis in one location before individual patents are taken in different
34 Poulton v. Adjustable Cover and Boiler Block Co., [1908] 2 Ch 430
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countries. This itself requires the Court, administering justice in
patent litigations, to stay abreast of, and if possible remain in sync
with, international legal practices. Of course, this would always be
subject to the international legal practice not being contrary to
municipal law applicable in, in our case, India. So long as applicable
of internationally accepted legal principles, practice and procedure, in
patent matters, does not conflict with Indian law, Courts should have
no hesitation in applying them.
66. We, therefore, feel no hesitation in applying, to our jurisdiction,
the law declared in Virgin Atlantic Airways.
67. We next turn to the definition of “patent”, as contained in the
Patents Act. Section 2(m) defines a “patent” as meaning “a patent for
any invention granted under this Act”. A patent, once granted,
therefore, remains a “patent” under the Patents Act, and does not
cease to remain a patent which was granted, even if it expires by
efflux of time. The expiry of the life of the patent merely renders it
unenforceable, and does not denude it of its character as a “patent
granted under” the Patents Act.
68. Applying, to the word “patent” in Section 64(1), therefore, the
definition of “patent” in Section 2(m), a patent remains a patent for
the purposes of Section 64(1), even after it expires.
69. In so far as the expression “person interested” in Section 64(1)
is concerned, we do not deem it necessary to enter deeply into the
etymological niceties of the expression, for the simple reason that
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Boehringer has itself filed the Himachal suit against Macleods. In
view of our finding that Macleods’ revocation, if it succeeds, would
invalidate Boehringer’s patent in the suit from inception, so that
Boehringer would not be able to seek either injunction or damages, it
is obvious that Macleods has a real and live interest in seeing that its
revocation petition succeeds. Macleods is, therefore, ex facie a
“person interested” within the meaning of Section 64(1).
70. These findings, in fact, should by themselves be dispositive of
the issue of whether a revocation proceeding can survive expiry of the
patent of which revocation is sought. Section 64 does not state
otherwise. Revocation, if granted, takes effect from the grant of the
patent being revoked. It is, therefore, rendered ineffective and
incapable of assertion ab initio. The interest of the revocation
petitioner, to ensure that the revocation succeeds, therefore, subsists,
and he remains a “person interested”.
71. Ergo, and per sequitur, the revocation petition would continue
to be maintainable even after the patent, of which revocation is
sought, expires.
72. The expiry of a patent, during the pendency of an infringement
suit, therefore merely changes the goal post. The remedy of
injunction, for the plaintiff, is lost, and the defendant, too, can rest
easy on that score. However, the plaintiff still retains the right to claim
damages for infringement which took place during the life of the
patent, and the defendant, too, therefore, has every right to, by way of
a counter-claim or a revocation petition as he may choose, seek
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revocation of the patent ab initio.
II. The decision in Aloys Wobben
73. Both sides have relied on the judgment of the Supreme Court in
Aloys Wobben. It becomes necessary, therefore, to examine the said
decision.
74. Dr. Singhvi and Mr. Sen have sought to contend that a
revocation petition could not be preferred after an infringement suit
had been filed. From this, it is also sought to be inferred that a
revocation petition, preferred prior to the institution of the suit, cannot
continue after the suit has been instituted or, at any rate, after the
patent of which revocation is sought has expired. This submission,
however, to our mind, selectively relies on the following sentence
from para 26 of report in Aloys Wobben:
“…..As such, “revocation petitions” filed later in point of time than
the institution of the “infringement suit”, would be unsustainable in
law…..”
75. We feel, with greatest respect to learned Senior Counsel, that
the sentence has been read out of context.
76. To the extent relevant, the facts in Aloys Wobben may be noted
thus. Aloys Wobben was a scientist-engineer and inventor. He filed
ten patent infringement suits, alleging that inventions patented in his
name had been infringed by, amongst others, Enercon India Ltd 35,
35 “Enercon” hereinafter
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before this Court. Subsequent thereto, Enercon filed a counter-claim,
seeking revocation of the Aloys Wobben’s patent. Enercon also filed
twenty three revocation petitions before the IPAB, praying for
revocation of the patents. The prayers in the revocation petitions and
the counter claim were identical, i.e. that the patent be revoked.
77. Despite some of the revocation petitions having been settled by
the IPAB, Enercon continued to prosecute its counter-claim in respect
of the same patents. This was the position which was before the
Supreme Court when it came to render its decision.
78. After extracting the relevant provisions, the Supreme Court
referred to Section 64 of the Patents Act and noted that it commences
with the words “subject to the provisions contained in this Act”. In
other words, Section 64 was subservient to all other provisions in the
Patents Act. The Supreme Court held, therefore, if there was any
provision in the Patents Act in conflict with the mandate contained in
Section 64, Section 64 would stand eclipsed and the other provisions
would govern. Para 18 of the report in Aloys Wobben, which sets out
this legal position, may be reproduced as under:
“18. Having heard the learned counsel, and having examined the
different provisions of the Patents Act relating to revocation of
patents, we shall now endeavour to examine the controversy in
hand. In our considered view, Section 64 of the Patents Act needs a
close examination. Section 64 aforementioned, is prefaced by the
words “Subject to the provisions contained in this Act,…”. And not
by the words, “Without prejudice to the provisions contained in
this Act …”, or “Notwithstanding the provisions contained in this
Act …”. The words with which the legislature has prefaced Section
64, necessarily lead to the inference, that the provisions contained
in Section 64 are subservient to all the other provisions contained
in the Patents Act. This exordium to Section 64 of the Patents Act
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mandates that the directive contained in Section 64 would be
subservient and deferential to the other provisions of the Patents
Act. Stated simply, if there is any provision under the Patents Act,
which is in conflict with the mandate contained in Section 64,
Section 64 of the Patents Act would stand eclipsed, and the other
provision(s) would govern the field under reference. Therefore, no
interpretation can be placed on Section 64 of the Patents Act which
will be in conflict with any other provision(s) of the Patents Act.”
(Emphasis supplied)
79. Section 64, therefore, “stands eclipsed” only if it is in conflict
with some other provision of the Patents Act.
80. In para 20 of the report, the Supreme Court noted that the
defendant in a patent infringement suit could raise a counter-claim,
questioning the validity of the asserted patent under Section 64. Thus,
Section 64 provided two remedies, one by way of a revocation petition
and the other by way of a counter-claim. In para 23 of the report, the
Supreme Court held that the use of the disjunctive “or” in Section 64
disentitled a defendant from filing both the proceedings for the same
purpose simultaneously. In the case before it, the Supreme Court
noted that Enercon had in fact availed both the remedies, and that the
issue to be considered was, therefore, the remedy which Enercon
should be permitted to pursue. Paras 25, 26 and 27.2 of the report in
Aloys Wobben set out the legal position, thus:
“25. …..Therefore, where an issue is already pending
adjudication between the same parties in a court having jurisdiction
to adjudicate upon the same, a subsequently instituted suit on the
same issue between the same parties cannot be allowed to proceed.
A similar question arises for consideration before this Court in the
present controversy. If the respondents in their capacity as “any
person interested”, had filed a “revocation petition” before the
institution of an “infringement suit”, they cannot be permitted to
file a “counterclaim” on the same cause of action. The natural
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of the patent would have to be determined in the “revocation
petition”. Therefore, in the above situation, while the “revocation
petition” will have to be permitted to be pursued, the
“counterclaim” cannot be permitted to be continued. Therefore, in
the above eventuality, it is apparent that the situation would be
resolved in the same manner as it would have been resolved in
cross-suits filed by the rival parties before different jurisdictional
courts. In our considered view, the above conclusion is imperative
for a harmonious interpretation of the relevant provisions of the
Patents Act.
26. In cases where the “infringement suit(s)” was/were filed by
the appellant herein (as plaintiff in the “infringement suit”), before
the “revocation petition(s)” was/were filed by the respondents (as
defendants in the “infringement suit”), the respondents had the
right to file “counterclaim(s)” to seek revocation of the patent
under the strength and authority emerging from Section 64(1) of
the Patents Act. Having once filed a “counterclaim” in response to
the “infringement suit(s)” on the same analogy as has been
recorded above, it would not be open to the respondents herein
(the defendants in the “infringement suits”) to file “revocation
petition(s)”, as they would likewise be barred by the rule of res
judicata. As such, “revocation petitions” filed later in point of time
than the institution of the “infringement suit”, would be
unsustainable in law. In such cases, the prayer for revocation of
the patent shall be adjudicated while disposing of the
“counterclaim” filed by the respondents. Therefore, in the above
situation, while the “counterclaim” will have to be permitted to be
pursued, the “revocation petition” cannot be permitted to be
continued.
*****
27.2. Secondly, if a “revocation petition” is filed by “any person
interested” in exercise of the liberty vested in him under Section
64(1) of the Patents Act, prior to the institution of an “infringement
suit” against him, he would be disentitled in law from seeking the
revocation of the patent (on the basis whereof an “infringement
suit” has been filed against him) through a “counterclaim”. This
denial of the remedy granted to him by way of a “counterclaim”
under Section 64(1) of the Patents Act, is based on the principle of
law narrated in para 25 above.”
(Emphasis supplied)
81. Thus, the Supreme Court has, in para 25 of Aloys Wobben, held
that, if a defendant, before the institution of the infringement suit, has
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already preferred a revocation petition seeking revocation of the suit
patent, it could not be permitted to file a counter-claim in the
infringement suit, as the invalidity of the suit patent would then have
to be tested in the revocation proceedings.
82. In para 26 of the report, the Supreme Court has addressed a
situation in which the defendant in the suit has filed a counter-claim
therein. In such a situation, the Supreme Court holds that it would not
be open to the defendant thereafter to file a revocation petition, as the
remedy sought in the counter-claim in the revocation petition is the
same and the revocation petition would be barred by res judicata.
83. It is in this context that, in para 26, it is held that the revocation
petition would not be maintainable. Mr. Nataraj is correct in his
emphasis on the words “as such” in para 26, which clearly link the
observations which follow to all these which precede the expression.
The observation that a revocation petition cannot be filed after an
infringement suit has been instituted is, therefore, clearly not stated as
an absolute proposition in para 26, but only if the defendant has
already filed a counter-claim in the said suit.
84. Para 27.2 of the report in Aloys Wobben deals with a situation
in which the revocation petition is filed prior to the institution of the
suit. In such a situation, as the same relief would be claimed in the
counter-claim, the Supreme Court has held that the defendant cannot,
after institution of the suit, prefer a counter-claim.
85. Aloys Wobben, therefore, does not address either the issue of
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whether a revocation petition can survive the expiry of the patent of
which it seeks revocation, or whether a revocation petition can be
filed after a Section 107 invalidity defence is taken by the defendant
in the infringement suit. The decision is, therefore, of no substantial
significance, in the facts of the present case.
III. Whether a revocation can be instituted, or can continue, after a
Section 107 invalidity defence is taken in an infringement suit
86. This issue, though really a no brainer, is partly answered by the
observations and findings supra, as well as the decision of the
Supreme Court in Aloys Wobben. Aloys Wobben, we may note at the
cost of repetition, clearly holds that revocation of the plaintiff’s patent
can, prior to the institution of an infringement suit, be sought by way
of a revocation petition, and, after the institution the infringement suit,
by way either of a revocation petition or of a counter-claim, but not
both. Neither does Aloys Wobben say that a revocation petition
cannot be filed after the infringement suit is instituted (as we have
already held hereinabove), nor does it say that a Section 107 invalidity
defence cannot simultaneously accompany a revocation petition, or a
counter-claim.
87. The issue, as raised by the appellant is, in fact, hardly an issue
at all. Revocation, and an invalidity defence under Section 107, are
fundamentally – and obviously – different. Revocation can, per
Section 64, be sought by way of a counter-claim. It would be
unknown to all principles of civil law and procedure to urge that a
defence taken in a written statement can, in any way, restrict the right
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of the defendant to independently file a counter-claim. And, if the
defendant can file a counter-claim, it can, equally, file, instead, a
revocation petition for the same relief, but not both simultaneously.
The right to file a revocation petition can, therefore, never be
impacted by the right to plead invalidity of the suit patent under
Section 107, as a defence to the infringement action.
88. There are any number of differences between a revocation
action under Section 64, and an invalidity defence under Section 107,
of which the following, correctly noticed by the learned Single Judge,
are self-apparent:
(i) A revocation petition, if it succeeds, removes the patent
entirely from the register of patents, and invalidates the very
grant of the patent. The patentee cannot, therefore, amend or
modify the patent, or assert it for any purpose. As against this, a
Section 107 plea is merely a defence in the infringement suit.
The highest that would result, if the defence succeeds, is that
the suit would be dismissed. The patent does not stand
removed, thereby, from the register of patents, even if the
defendant may, in another proceeding in which, hypothetically,
the same patent is asserted, rely on the decision in the earlier
suit.
(ii) It is for this reason that Section 151 requires the decision
on the revocation petition to be transmitted to the Controller of
Patents, and requires the Controller to make an entry in that
regard in the register of patents, whereas the decision on a
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Section 107 invalidity defence is, though transmitted to the
Controller, only required to be entered in a supplemental
record.
(iii) The decision on an invalidity defence under Section 107
operates in personam, whereas the decision in a revocation
petition under Section 64 operates in rem. This position stands
recognized even in Virgin Atlantic Airways.
89. Dr. Singhvi’s submission that allowing a revocation petition to
continue even after an invalidity defence has been raised under
Section 107 would result in multiplicity of litigation, therefore,
obviously cannot be accepted. The two operate in different spheres.
Till the patent is revoked, it continues to remain valid and
enforceable, and the cause of action for raising the Section 107
invalidity defence, too, therefore, subsists. There is, therefore, no
question of multiplicity of litigation.
G. Conclusion
90. We therefore, agree with the learned Single Judge on both the
issues framed by him. More particularly, we hold that
(i) a revocation petition would be maintainable, and would
continue to survive, even after the patent of which revocation is
sought expires by efflux of time, and
(ii) a revocation petition can be instituted even after a
Section 107 invalidity defence is taken in the infringement suit.
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91. The appeal, therefore, fails and is dismissed, with no orders as
to costs.
92. We appreciate the assistance rendered by learned Counsel in
resolving an issue for which there was no ready legal precedent.
C. HARI SHANKAR, J.
OM PRAKASH SHUKLA, J.
FEBRUARY 24, 2026
DSN/AR
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