Summary of the Judgment
I.

Main text
1. The defendant shall not manufacture or sell the Defendant’s Styluses.
2. The remaining parts of the plaintiff’s demand are dismissed with prejudice on
the merits.

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3. The court costs shall be divided into two equal parts, with the defendant tobear one half and the plaintiff to bear the other half.
4. This judgment may be provisionally enforced as far as paragraph 1 isconcerned.
II. Outline of the Case10

1.

The plaintiff is a holder of the Present Patent for an invention named“Position detector.” The defendant manufactures and sells position detectors
with the product name “D-Pointer” bearing model code “D-10” (the“Defendant’s Position Detector(s)”). The plaintiff asserts that the manufacture

15and sale of the Defendant’s Position Detectors and replaceable styluses (the“Defendant’s Stylus(es)”) by the defendant constitute indirect infringement of
the Present Patent (as set forth in item (i) or (ii), Article 101 of the Patent Act).
The plaintiff seeks an injunction pursuant to paragraph (1), Article 100 of thePatent Act to demand that the defendant halt the manufacture and sale of the20Defendant’s Position Detectors and the Defendant’s Styluses.
2. (1) Descriptions of the scope of claims
Claim 1 of the Present Patent is described as follows. The invention
claimed in Claim 1 is hereinafter referred to as the “Present Invention.”<Claim 1>

25.

A position detector comprising:A.

a micro-movable stylus held in a predetermined stable position1

in an electrically insulated state; anda main body including a contact detection circuit connected tothe stylus,
wherein contact between the stylus and a workpiece iselectrically detected as a result of formation of a closed circuit5including the contact detection circuit via the workpiece when acontacting portion of the stylus contacts the workpiece, andB.

wherein the contacting portion of the stylus is made of a nonmagnetic material containing tungsten carbide and a nickel binder.

10(2) Fulfillment of the Elements of the Present Invention
Since the Defendant’s Position Detector equipped with the standard
stainless steel stylus (Form α) fulfills Feature A but does not fulfill “FeatureB,” the Defendant’s Position Detector in Form α does not fall within thetechnical scope of the Present Invention.
On the other hand, the Defendant’s Position Detector equipped with15

the Defendant’s Stylus (Form β) falls within the technical scope of thePresent Invention since it fulfills all the elements of it.
3. The points at issue in this case are as follows.
(1)
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Whether or not the manufacture and sale of the Defendant’s Stylusesby the defendant constitute indirect infringement as set forth in item (i),Article 101 of the Patent Acta) Does the Defendant’s Stylus fall under “any product to be used
exclusively for the producing of” the Defendant’s Position Detector inForm β?

25b) Do the manufacture and sale of the Defendant’s Styluses fall under“producing, assigning” “any product to be used exclusively for the2

producing of the said product”?
(2)

Whether or not the manufacture and sale of the Defendant’s Stylusesby the defendant constitute indirect infringement as set forth in item (ii),Article 101 of the Patent Acta) Does the Defendant’s Stylus fall under “any product (excluding those5

widely distributed within Japan) to be used for the producing of” theDefendant’s Position Detector in Form β and a product that is“indispensable for the resolution of the problem” by the PresentInvention?
b) Do the manufacture and sale of the Defendant’s Styluses fall under an10

act of “producing, assigning … any product … knowing that … the said
product is used for the working of the invention”?
(3)

Whether or not the manufacture and sale of the Defendant’s Position
Detectors by the defendant constitute indirect infringement as set forth in15

item (ii), Article 101 of the Patent Acta) Does the Defendant’s Position Detector fall under “any product(excluding those widely distributed within Japan) to be used for theproducing of” the Defendant’s Position Detector in Form β and a
product that is “indispensable for the resolution of the problem” by the20

Present Invention?
b) Do the manufacture and sale of the Defendant’s Position Detectors
fall under an act of “producing, assigning … any product … knowingthat … the said product is used for the working of the invention”?
(4) Necessity of injunction against the manufacture and sale25

III. Summary of the Determinations concerning the Points at Issue
1. Whether or not the manufacture and sale of the Defendant’s Styluses by the3

defendant constitute indirect infringement as set forth in item (i), Article 101 of
the Patent Act(1)Item (i), Article 101 of the Patent Act provides, as one of therequirements for establishing indirect infringement, “any product to beused exclusively for the producing of the said product,” which is

5interpreted as an attempt to expand the scope of infringement of a patentright in such a way as to cover only the acts that are highly likely to induce
direct infringement, with a view to ensuring the effect of a patent rightwithin such range that will not unduly enlarge the effect of a patent right.
Therefore, in order for the plaintiff to assert that an article at issue falls

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under “any product to be used exclusively for the producing of the saidproduct” as set forth in item (i), Article 101 of the Patent Act, in a situation
where the article is available for use in both forms that is for the workingof the patented invention and that is not, the plaintiff must prove that theuse of the article in a form not for the working of the patented invention is15

not an economical, commercial or practical application of that article.
(2)

Let us apply the foregoing theory to this case. If a user attaches theDefendant’s Stylus to the Defendant’s Position Detector to make it into theDefendant’s Position Detector in Form β, the user’s act falls under “the20

producing of” the Defendant’s Position Detector which falls within thetechnical scope of the Present Invention as an invention of a product.
The Defendant’s Stylus is compatible not only with the Defendant’sPosition Detector, but also with the internal contact type position detector
manufactured by the defendant, and can be used by attaching it to that25

type of position detector. The internal contact type position detector
equipped with the Defendant’s Stylus does not fall within the technical4scope of the Present Invention, thus the act of using the Defendant’s
Stylus applied to the internal contact type position detector shall beconsidered as use in a form not for the working of the Present Invention.
In this case, no sufficient evidence is found to determine that the use insuch a way is not an economical, commercial or practical application of5

the Defendant’s Stylus. On the contrary, the Defendant’s Stylus has
excellent abrasion resistance and corrosion resistance, and so, evenwhen it is applied to the internal contact type position detector, anadvantage of preventing measurement errors resulting from wear anddeformation caused by repeated contact with workpieces can be

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recognized. Therefore, using the Defendant’s Stylus in such a way is an
economical, commercial or practical application of it.
Consequently, the Defendant’s Stylus does not fall under “anyproduct to be used exclusively for the producing of” the Defendant’sPosition Detector in Form β. The remaining points asserted as to this issue

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need not to be determined. In conclusion, the manufacture and sale of theDefendant’s Styluses by the defendant do not constitute indirect
infringement as set forth in item (i), Article 101 of the Patent Act.
2. Whether or not the manufacture and sale of the Defendant’s Styluses by the20

defendant constitute indirect infringement as set forth in item (ii), Article 101of the Patent Act(1)

First, attaching the Defendant’s Stylus to the Defendant’s Position
Detector falls under “the producing of” the Defendant’s Position Detector
in Form β. Unlike versatile products such as screws or nails, it is found25

that the Defendant’s Stylus is a specially designed product compatible
exclusively with the position detector manufactured by the defendant.

5Therefore, the Defendant’s Stylus does not fall under “those widelydistributed within Japan.” This means that the Defendant’s Stylus falls
under “any product (excluding those widely distributed within Japan) to be
used for the producing of” the Defendant’s Position Detector in Form β.
5Next, the Specification of the Present Patent discloses the following.
A conventional position detector had a disadvantage of causing ameasurement error in detecting the position of a magnetic workpiece when
the stylus is magnetized. In addition, a conventional stylus made of a nonmagnetic metal material had a disadvantage that it generally had low

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hardness, and wear and deformation caused a measurement error. The
Present Invention therefore aims at providing position detectors enabling
accurate position detection equipped with a stylus which is durable anddoes not cause a measurement error. As a means for solving this problem,
the Present Invention adopts the structure that, in an energized type15

position detector, a contacting portion of the stylus is made of a nonmagnetic material containing tungsten carbide and a nickel binder, bywhich the Present Invention has the effect of preventing the stylus frombeing magnetized by opening and closing a contact detection circuit, as
well as the effect of preventing deterioration of position detection accuracy

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due to wear or deformation of the contacting portion and enabling accurate
position detection.
Since the Defendant’s Stylus has the same structure as the one
described above that is a means to solve the above problem by thePresent Invention, it shall be considered to fall under “any product … to25

be … indispensable for the resolution of the problem” by the PresentInvention.

6As a consequence, the Defendant’s Stylus falls under “any product(excluding those widely distributed within Japan) to be used for theproducing of” the Defendant’s Position Detector in Form β” and a product“indispensable for the resolution of the problem.”5(2)It is found that on May 1, 2020, the defendant was notified by theplaintiff of the contents of the Present Invention, that the Defendant’sPosition Detector with the Defendant’s Stylus attached falls within thetechnical scope of the Present Invention and that the manufacture andsale of the Defendant’s Styluses constitute infringement of the Plaintiff’sPatent Right. The defendant is therefore found to have become aware by

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that day that the Present Invention is a patented invention and that it ishighly probable that the Defendant’s Stylus is used for the working of thePresent Invention.
In consequence, the manufacture and sale of the Defendant’sStyluses by the defendant shall be considered to fall under acts of

15“producing, assigning … any product … knowing that the said product isused for the working of the invention.”(3)

Based on the foregoing, the manufacture and sale of the Defendant’s
Styluses by the defendant shall be considered to constitute indirect
infringement as set forth in item (ii), Article 101 of the Patent Act.

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3. Whether or not the manufacture and sale of the Defendant’s Position
Detectors by the defendant constitute indirect infringement as set forth in item(ii), Article 101 of the Patent Act(1)
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The plaintiff asserts that, to solve the problem by the Present
Invention, both adopting the energized type measurement method of theposition detector and making the stylus of a non-magnetic material are7

indispensable, then the Defendant’s Position Detector is also an article
that is “indispensable for the resolution of the problem” by the Present
Invention in the composition of the Defendant’s Position Detector with theDefendant’s Stylus attached (Form β).
As stated above, however, the Present Invention aims at5providingposition detectors enabling accurate position detection equipped with astylus which is durable and does not cause a measurement error. As ameans for solving this problem, the Present Invention adopts “thestructure that, in an energized type position detector, a contacting portionof the stylus is made of a non-magnetic material containing tungsten

10carbide and a nickel binder”. On the other hand, the main body of theDefendant’s Position Detector is an independent component that differsfrom the Defendant’s Stylus adopting the structure described above.
Therefore, the main body shall not be an article “indispensable for theresolution of the problem” by the Present Invention.

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Inconsequence,

theplaintiff’s

aforementionedassertion

isgroundless.
(2)

Based on the above, the Defendant’s Position Detector does not fallunder “any product … to be indispensable for the resolution of the problem”20by the Present Invention. The remaining points asserted as to this issue
need not to be determined. In conclusion, the manufacture and sale of theDefendant’s Position Detectors by the defendant do not constitute indirect
infringement as set forth in item (ii), Article 101 of the Patent Act.
4. Necessity of injunction against the manufacture and sale25

The defendant asserts that, since the Defendant’s Stylus has other legal
uses than being applied to the Defendant’s Position Detector, injunction to8

completely prohibit the manufacture and sale of the Defendant’s Styluses isexcessive, and that there is no need for such injunction.
However, the court recognizes the following facts. First, the Defendant’s
Stylus is sold as a replacement for the stylus attached to the Defendant’s
5Position Detector as standard equipment. Second, while the Defendant’s
Stylus has other uses than being applied to the Defendant’s Position Detector,
the Defendant’s Stylus is an article indispensable for solving the problem by
the Present Invention, and present circumstances show it is highly probablethat acts such as assigning the Defendant’s Styluses may induce infringement

10of the Plaintiff’s Patent Right. In light of these facts, the necessity of injunction
against the manufacture and sale of the Defendant’s Styluses shall berecognized for the purpose of stopping and preventing infringement of thePlaintiff’s Patent Right.
Therefore, the defendant’s aforementioned assertion shall not be admitted.

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5. Conclusion
Based on all of the foregoing, the plaintiff’s claim has a ground and shallbe upheld to the extent of seeking the injunction against the manufacture andsale of the Defendant’s Styluses. The remaining parts of the plaintiff’s claim
shall be dismissed as groundless. Therefore, the court renders a judgment as20

indicated in the main text.

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