7.5.4 Defense of correction
When a defense of invalidity is asserted by a defendant in patent infringement proceedings, the plaintiff (the patentee) may be able to avoid invalidity by asserting a defense of correction – that the grounds for invalidity can be addressed by either a final and binding JPO correction decision or a request for a correction. Therefore, in parallel with this, the alleged infringer can assert the effect of the correction in a suit for infringement of a patent.
7.5.4.1 Four requirements and an exception
The following four requirements must be satisfied for a defense of correction:
- The request for correction (where a trial for invalidation is pending) or the request for a trial of correction by the JPO (where a trial for invalidation is not pending) must be lawful.222
- The correction meets the correction requirements – that is, no new matter has been added.
- The reason for invalidation alleged in the defense of invalidity is resolved by the correction.
- The defendant’s product (or process) falls within the technical scope of the patented invention after correction.
However, in relation to the first requirement, under the Patent Act, there is period in which a request for neither a correction nor for a trial for correction can be made, and so the IP High Court has ruled that
when it is legally difficult for a patentee to file a request for correction etc., such circumstances should be taken into consideration on a case-by-case basis from the standpoint of fairness, and when there are special circumstances that do not require the filing of a legal request for correction etc., the patentee may be allowed to make an allegation of defense of correction without satisfying such requirement.223
In this regard, the IP High Court has held that
if such request cannot be made because the patentee’s right to request correction or request a trial for correction is restricted, a declaration to the effect that such request for correction (or a request for a trial for correction) will be made when it “becomes possible” is sufficient.224
In addition, the IP High Court has also held that
the appellant could request neither a correction nor a trial for correction until receiving a notice of the trial decision from the JPO under Article 126, paragraph (2), Article 134-2, paragraph (1) of the Patent Act. Under such circumstances, the appellant does not need to make these requests to the JPO in order to assert the defense of correction.225
Accordingly, it is still possible to assert the defense of correction even during the term when it is not possible to request a correction or a trial for correction under the Patent Act. However, the patentee will need to request a correction or trial for correction at the JPO when it becomes possible to do so under the Patent Act.
A patentee is required to assert a defense of correction before the conclusion of the oral hearing of the IP High Court at the latest so as not to cause a delay, irrespective of the progress of the hearing proceedings before the JPO. Otherwise, it will be impossible to assert a defense of correction when a correction or a trial for correction may be requested under the Patent Act.226 A patentee should be mindful of this timing issue.
7.5.4.2 When to assert the defense
The defense of correction will be dismissed if it is late or if it will unduly delay the proceedings.227 For example, the IP High Court has dismissed a defense of correction submitted four days before the first hearing date of an appeal trial because “it was possible to the assert the defense of correction by the due date of the first brief before the IP High Court.”228
7.5.4.3 Consent of joint owner and exclusive licensee
Under the Patent Act, a patentee may only request a trial for correction with the consent of any joint owners and exclusive licensees.229 Further, the Tokyo District Court has also rejected a patentee’s defense of correction assertion to which a nonexclusive licensee did not consent.230
7.5.4.4 Patentee failure to request correction or trial for correction
As noted above, the defense of correction usually requires that a lawful request for correction or a trial of correction has been made with the JPO.231 However, the IP High Court has indicated that this is not necessary during the period when neither a correction nor a trial for correction may be requested under the Patent Act. In these circumstances, the patentee is required to file a request for correction or a trial for correction at the JPO when it becomes possible to do so under the Patent Act.
However, there is a risk that this could lead to complexity and undesirable outcomes. For example, it could lead to a situation wherein a patentee asserts the defense of correction (without first requesting a correction or a trial for correction) and is successful in a patent infringement lawsuit as a result of asserting this defense but does not request a correction or a trial for correction with different claim wording with the JPO, even when it becomes possible to do so under the Patent Act.
There is some debate as to the type of penalty that could be imposed on the patentee in such a situation and whether a defendant could seek a retrial of a patent infringement lawsuit that has already become final and binding. However, there are no court cases that consider this point, and the debate is still developing