April, 2019｜News Letter

1. How Much can Decision on Inventive Step be Affected by Level of Comprehension of Common Technical Knowledge?

Nipro Corporation v. Chiba University and Fuso Pharmaceutical Industries, Ltd., Case No. 2018 (Gyo-Ke) 10061 (Decision rendered on April 25, 2019)

The Patentees, Chiba University and Fuso Pharmaceutical Industries (C&F), obtained a patent relating to a drug solution of mixing type in 2013. Against the C&F’s patent, Nipro filed an invalidation trial with the JPO in 2017. During the trial procedure, C&F demanded a correction of the claims. The JPO admitted the correction, and rendered a decision of dismissing the Nipro’s demand in 2018. Nipro filed an appeal against the JPO’s decision with the IPHC in 2018.

The corrected Claim 1 of the C&F’s patent at issue claims as follows:
A drug solution of mixing type on use for acute blood purification, which comprises:
a Solution A comprising sodium ion, chloride ion, bicarbonate ion and water, and
a Solution B comprising sodium ion, calcium ion, magnesium ion, chloride ion, glucose and water;
wherein at least one of the Solution A and the Solution B further comprises potassium ion, and both the Solution A and the Solution B comprise no acetate ion;
wherein a potassium ion concentration is 4.0 mEq/L, an inorganic phosphorus concentration is 4.0 mg/dL, a calcium ion concentration is 2.5 mEq/L, a magnesium ion concentration is 1.0 mEq/L and a bicarbonate ion concentration is 32.0 mEq/L; and
wherein a formation of insoluble fine particles or precipitates is substantially prevented at least for 27 hours.
<The corrected part is underlined>

One of the main issues in this case related to how much the decision on inventive step can be affected by the level of comprehension of common technical knowledge. The IPHC answered to the issue as follows:

In the JPO’s decision, the JPO found that there were 6 substantial differences between the corrected Claim 1 of the patent at issue (“present invention”) and the invention disclosed in Exhibit A-3 (“cited invention”) in (a) that sodium ions are contained in both the Solution A and the Solution B in the former, while the ions are contained only in the first single solution <Difference 1>; (b) that the former specifies that a formation of insoluble fine particles or precipitates is substantially prevented at least for 27 hours, while the latter does not specify such a formation <Difference 3>; (c) that the former relates to a drug solution of mixing type on use for acute blood purification, while the latter relates to a medical solution <Difference 4>; (d) that the inorganic phosphorus concentration is 4.0 mg/dL in the former, while the concentration is calculated to be 3.72 mg/dL in the latter <Difference 6>; (e) that the magnesium ion concentration is 1.0 mEq/L in the former, while the concentration is calculated to be 1.2 mEq/L in the latter <Difference 7>; and (f) that the bicarbonate ion concentration is 32.0 mEq/L in the former, while the concentration is calculated to be 30.0 mq/L in the latter <Difference 8>.
On the basis of the above findings, the JPO determined that those skilled in the art could not have easily conceived any of Differences (a) to (f).

However, the IPHC completely overturned the above JPO’s decision as follows:
The IPHC first reviewed Exhibit A-10 in detail, and found that it was common technical knowledge or well known (i) that commercially available dialysate and substitution liquid may be used in blood filtration (dialysis) for “acute blood purification”; (ii) that compositions of commercially available dialysate and substitution liquid include sodium ions, potassium ions, calcium ions, magnesium ions, and bicarbonate ions, and these electrolytes are required to maintain concentrations in blood in extremely narrow ranges, and therefore certain levels of concentration are predetermined; and (iii) that, in commercially available dialysate and substitution liquid, concentration of calcium ions is adjusted in a range of around “2.5 to 3.5 mEq/L”, that of magnesium ions in a range of around “1.0 to 1.5 mEq/L”, and that of bicarbonate ions in a range of around “30 mEq/L”.
Taking into consideration the above findings belonging to common technical knowledge, the IPHC decided on Differences 1, 3, 4, 6, 7 and 8 as follows:

(A) As to Difference 1
In light of matters described in Exhibit A-3, it is a matter of design choice that those skilled in the art could have adequately selected to have a constitution where sodium ions are compounded as usual in both the first single solution and the second single solution.

(B) As to Difference 4
In light of matters disclosed or described in Exhibit A-3, the “medical solution” of the “cited invention” which is an working example of the “cited invention” could be understood to be administrable to patients affected with acute renal failure. Therefore, those skilled in the art having regard to Exhibit A-3 would have the motivation to attempt to administer the “medical solution” of the “cited invention” as the “drug solution for acute blood purification of mixing type on use”.

(C) As to Difference 6
Exhibit A-3 discloses or describes the following aspects:
(1) One of the objects of the “cited invention” is to provide a “medical solution” that ensures good stability, both during storage and during use, that contains no precipitates and is sterile.
(2) The inventors of the “cited invention” have found that calcium ions and magnesium ions under certain conditions, such as specific pH ranges, could be kept together with bicarbonate salts, and under certain conditions could be kept together also with phosphate, and that a medical solution containing sterile and stabile phosphate could be provided under specific circumstances, concentrations, pH ranges and packaging.
(3) In order to solve the problem mentioned above, the “cited invention” adopted a constitution where the ready-for-use solution comprises phosphate in an inorganic phosphorus concentration of “3.1 to 8.7 mg/dL”, is sterile and has a pH of 6.5 to 7.6.
(4) It should be understood that various changes and modifications to the presently preferred embodiments described in the specification of the “cited invention” can be made without departing from the spirit and scope of the “cited invention” and without diminishing its attendant advantages.
As such, those skilled in the art having regard to Exhibit A-3 would have the motivation to attempt to adjust the inorganic phosphorus concentration of the “cited invention” to fall within the range mentioned above in (3) in order to obtain the medical solution containing sterile and stabile phosphate.

(D) As to Differences 7 and 8
In light of matters disclosed or described in (C) mentioned above, those skilled in the art having regard to Exhibit A-3 would understand that the ion concentration of each component of the ready-for-use solution in the “cited invention” could be changed to an optimum.
Whereas, at the time of the priority date of the “present application”, in a commercially available dialysate and substitution liquid that could be used in blood filtration (dialysis) for acute blood purification, it was common technical knowledge or well-known to adjust the magnesium ion concentration in a range of around “1.0 to 1.5 mEq/l” and the bicarbonate ion concentration in a range of around “30 mEq/l”. Therefore, it is a matter of design choice that those skilled in the art could have adequately selected to adjust the magnesium ion concentration and the bicarbonate ion concentration of the “cited invention” to fall within the numerical ranges mentioned above.

(E) As to Difference 3
Comprehensively considering the recitations of Claims (the corrected claim 1) of the “present invention” and the descriptions of the present specification, the constitution of the “present invention” according to Difference 3 could be understood to be achieved by specifying the component compositions of Solution A and Solution B of the “present invention” and the ion concentrations thereof as those recited in the corrected claim 1. Therefore, the constitution of the “present invention” according to Difference 3 would be naturally met in the case of the “cited invention” where the constitutions of the “present invention” according to Differences 1, 4, and 6 to 8 are met.

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

An appeal to the Supreme Court was filed against this decision, and thus the decision is NOT made final and binding.

K&P’s Comments As shown in the above decision, all of the decisions on inventive step regarding 6 Differences were completely overturned depending on the comprehension of common technical knowledge even on the basis of the same main cited invention. Namely, the above decision teaches that it is quite important and even critical in some cases to determine what is common technical knowledge in examining inventive step.

(by Katsumasa OSAKI, Patent Attorney)

In April, 2019, the IPHC handed down 10 decisions including the above case on patent and utility model, and overturned the previous decisions in 5 cases.

In April, 2019, the IPHC handed down no decisions on trademark.

In April, 2019, the IPHC handed down 4 decisions on industrial design, and maintained all the previous decisions.