Recently, we have observed a growing number of toilet rolls products with extended roll lengths without excessively increasing the roll diameter. Consumers are drawn to the convenience of these products, which offer less frequent toilet roll changes and reduce storage space. At present, such products account for approximately 30% of the market. Pulp and paper companies are applying their ingenuity to enhance sheet softness, as longer-length toilet rolls contain more layers.
On October 8, 2025, the Intellectual Property High Court (IPHC) dismissed Nippon Paper Crecia’s (Crecia) claim that Daio Paper (Daio) had infringed its patent relating to triple-length toilet rolls, thereby upholding the Tokyo District Court’s (TDC) earlier ruling that found no patent infringement.
Daio announced that the case had concluded, as Crecia did not file a petition for acceptance of appeal following the IPHC’s dismissal of the case. It was recognized that Crecia’s patents do not cover Daio’s products. Before the IPHC, the court examined the issue of whether the depth of the surface embossing employed to achieve softness falls within the numerical ranges specified in the patents.
Overview of the case
Title of invention / Japanese patent registration number
[Present invention 1] Toilet roll / JP6735251
Present invention 1 is characterized by numerical ranges, such as the depth of embossing on the sheet.
[Present invention 2] Roll product package / JP6590596
Present invention 2 is characterized by a package containing multiple toilet rolls, defined by the shape of the grip section of the packaging bag, its dimensions, and the weight of the toilet rolls.
[Present invention 3] Toilet roll / JP6186483
Present invention 3 is characterized by numerical ranges, such as the depth of embossing on the sheet.
Appellant (Plaintiff): Crecia
Appellee (Defendant): Daio
Case number: 2024(Ne)10069
Type of the case: Request for injunction against patent infringement
Original trial case number: 2022(Wa)22517, Tokyo District Court
Date of judgment: October 8, 2025
Amount of compensation: 33 million JPY
Crecia sells triple-length toilet rolls under the brand name “Scottie”. By 2020, Crecia had obtained the three patents mentioned above, relating to technologies for packaging and the embossing depth on the surface of toilet paper rolls. In contrast, Daio sells toilet rolls that are 3.2 times longer than conventional products under the brand name “Elleair”. Crecia asserted that the embossing depth on Elleair ’s sheets fell within the predetermined ranges specified in its patents. Accordingly, in 2022, Crecia filed an action before the TDC, seeking an injunction on manufacturing and sales, as well as compensation for damages, against Daio.
The TDC Decision
At the first instance, the TDC ruled that there was no patent infringement. Present inventions 1 and 3 feature specific dimensions of embossing. However, the TDC determined that the measurement method presented in the evidence submitted by Crecia was not based on the measurement method described in the patent specification. In addition, the court found that the peripheral edges of the embossing, which serve as the basis for determining embossing dimensions, were ambiguously defined. Consequently, the TDC concluded that the depth of embossing pattern on Daio’s product could not be determined to fall within the numerical ranges specified in Crecia’s patented inventions. Regarding present invention 2, the TDC found that Daio’s product packaging did not conform to the configuration defined by Crecia’s patented invention, noting differences in the shape of the slit formed at the edge of the packaging bag. Furthermore, the TDC denied infringement of present inventions 1, 2, and 3 under the doctrine of equivalents.
The IPHC Decision
At the appeal in the IPHC, Crecia submitted additional evidence showing results of new measurements of the embossing depth based on a revised measurement method, modifying the measurement method which the TDC had pointed out its inaccuracy. However, the IPHC found that the revised measurement method in the evidence was still based on the measurement method described in the specification, and that the periphery of the embossing remained ambiguously defined. As a result, the IPHC rejected the appeal, holding that the numerical ranges of Daio’s products did not fall within the scope of the patents, even when the evidence is taken into account. Following the first-instance ruling, the IPHC found no patent infringement and dismissed the suit.
Key Takeaways for Practitioners
The above IPHC decision clarifies that a patentee must explicitly describe the measurement method in the specification to determine whether a numerical value of an accused product falls within the specified numerical range. Even if a party contends that the value of the accused product falls within the numerical range based on a measurement method different from that described in the specification, such assertion is likely to be rejected. Moreover, in cases where patent claims set multiple numerical ranges limitations determined in the specification, infringement can be negated if any one of those limitations is not satisfied. From the competitors’ standpoint, it would be therefore advisable to design their products from the design stage so that they fall outside the numerical ranges, thereby avoiding infringement findings (including those based on the doctrine of equivalents). Additionally, challenging the measurement method used to determine whether a value falls within the numerical range may provide an effective counterargument.
Patent invention with numerical range limitation
This refers to a situation where a part of the patent claims is limited by a range of specific numerical values as specific features of the invention.