July, 2019｜News Letter

1. What Range of Effect should be Presented in Examining Inventive Step?

Naigai Chemical Products Co., Ltd. v. Mitsubishi Gas Chemical Company Inc., Katayama Chemical Ltd., and Nalco Japan GK; Case No. 2018 (Gyo-Ke) 10145 (Decision rendered on July 18, 2019)

The Patentee, Mitsubishi Gas Chemical et al. (Mitsubishi et al.), obtained a patent relating to a method for preventing adhesion of marine organisms in 2016. Against the Mitsubishi et al.’s patent, Naigai Chemical Products (Naigai) filed an invalidation trial with the JPO in 2017. The JPO dismissed the Naigai’s demand in 2018. Naigai filed an appeal against the JPO's decision to the IPHC in 2018.

Claim 1 of the Mitsubishi et al’s patent at issue claims as follows:
A method for preventing adhesion of marine organisms,
comprising adding chlorine dioxide and hydrogen peroxide in this order or in the reverse order, or simultaneously into sea water in a sea-water cooling water system to allow the chlorine dioxide and the hydrogen peroxide to coexist in the sea water, and thereby preventing adhesion of the marine organisms to the sea-water cooling water system.

One of the main issues in this case related to what range of effect should be presented in examining　inventive step.

The IPHC answered to the issue as follows:

To begin with, in the JPO’s decision, the JPO found that there was one difference between Claim 1 of the patent at issue and the invention disclosed in prior art reference (p.a.r.) 1 in that chlorine dioxide is further added in addition to hydrogen peroxide in this order or in the reverse order, or simultaneously into sea water so that the chlorine dioxide and hydrogen peroxide coexist in the sea water in the former, while an effective chlorine generating agent is further injected simultaneously or alternately into sea water in the latter, and determined that those skilled in the art could not have easily conceived the difference, and even if the difference was easily conceivable, Claim 1 showed a remarkable effect that those skilled in the art could not have expected.

However, the IPHC overturned the above JPO’s decision as follows:

The IPHC first reviewed p.a.r.s 1 to 3 and 5 in detail, and acknowledged (i) that those skilled in the art having regard to the p.a.r.s could have recognized that the invention disclosed in p.a.r. 1 where hydrogen peroxide and an effective chlorine generating agent are used in combination has a problem of generating harmful trihalomethane by adding the effective chlorine generating agent, and therefore (ii) that there is a motivation to try to replace the effective chlorine generating agent used in p.a.r. 1 with chlorine dioxide disclosed in p.a.r. 2 to avoid generating trihalomethane in solving the problem.

Further, the IPHC reviewed the Examples of the patent at issue, in particular, Tests 1, 4 and 5, in detail, and determined on a remarkable effect as below:

(1) As to Test 1
Table 1 shows the results of Test 1 that includes working examples 1 and 2 and comparative examples 1 and 2, and from Table 1, it can be understood that the residual rate of chlorine dioxide, when chlorine dioxide and hydrogen peroxide are added to filtrate sea-water, varies over a wide range depending on the concentrations of chlorine dioxide and hydrogen peroxide and the addition order, whereas Claim 1 does not define the concentrations of chlorine dioxide and hydrogen peroxide and the addition order, and thus it cannot be acknowledged that the results of Test 1 show the effect in the whole range of Claim 1. Accordingly, it cannot be acknowledged from Test 1 that Claim 1 shows a remarkable effect.

(2) As to Test 4
(A) Table 4 shows the results of Test 4 that includes working example 1 and comparative example 4, and the results of the comparison of working example 1 and comparative example 4 shows that the result when chlorine dioxide and hydrogen peroxide are used in combination is 3 times better than that when sodium hypochlorite and hydrogen peroxide are used in combination, whereas, as stated above, it can be understood that the residual rate of chlorine dioxide when chlorine dioxide and hydrogen peroxide are added to sea water varies over a wide range depending on the concentrations of chlorine dioxide and hydrogen peroxide and the addition order, and in association with the variation, the effect of preventing adhesion of slime and the like can vary. Accordingly, it cannot be acknowledged that the results of Test 4 show the effect in the whole range of Claim 1.
(B) From the working example 2 of p.a.r. 2, it can be understood that the reduction amount of slime when 3 ppm of sodium hypochlorite is used approximately corresponds to that when 0.1 ppm or less of chlorine dioxide is used, and thus chlorine dioxide shows a similar effect of preventing adhesion of slime with a considerably lower amount thereof than that of sodium hypochlorite.

Accordingly, those skilled in the art having regard to p.a.r.s 1 and 2 could have expected that a better effect of preventing adhesion of slime would be obtained when an effective chlorine generating agent disclosed in p.a.r. 1 is replaced with chlorine dioxide and chlorine dioxide and hydrogen peroxide are used in combination rather than to use sodium hypochlorite and hydrogen peroxide in combination, and thus it cannot be acknowledged that the results of Table 4 show an unexpected effect.

(3) As to Test 5
(A) Table 5 shows the results of Test 5 that includes working example 1 and comparative example 4, and the results of the comparison of working example 1 and comparative example 4 show that the result when chlorine dioxide and hydrogen peroxide are used in combination is more than 3 times better than that when the same concentrations of sodium hypochlorite and hydrogen peroxide are used in combination, whereas, for the same reason as stated above, it cannot be acknowledged that the results of Test 5 show the effect in the whole range of Claim 1.
(B) For the same reason as stated above, it can be understood from p.a.r. 2 that chlorine dioxide can bring about the effect of preventing adhesion of marine organisms with a considerably lower concentration than that of sodium hypochlorite. Accordingly, it cannot be acknowledged that the results of Table 5 show that Claim 1 brings about an effect that those skilled in the art could not have expected.

Conclusively, the IPHC upheld the Naigai’s appeal and cancelled the JPO’s decision.

An appeal to the Supreme Court was filed against this decision, but the appeal was withdrawn, and thus the decision is made final and binding.

K&P’s Comments As shown above, the IPHC did not acknowledge an unexpected remarkable effect, which is one of the very important factors for considering inventive step under the Japanese practice, on the basis of the effect brought about from only a part of the claimed invention. Rather, the IPHC seems to require showing that such an effect can be brought about in the whole range of the claimed invention, which we believe is overly severe.

(by Katsumasa OSAKI, Patent Attorney)

In July, 2019, the IPHC handed down 10 decisions including the above case on patent, and overturned the previous decisions in 3 cases.

In July, 2019, the IPHC handed down 3 decisions on trademark, and overturned the previous decision in 1 case.

In July, 2019, the IPHC handed down 1decision on industrial design, and maintained the previous decision.