21

Article 103 of the Patent Act and Duty of Care underLiability Law－Review of Provisions on Presumption of Negligence
under Industrial Property Right Law－（*）
Research Fellow: Miyuki Tsuyuki

The purpose of this study is to discover problems included in Article 103 of the Patent Act in modern society
and the ideal obligation of patent search through study of the legislative history, the meaning of legislation, andactual operation of the provisions on presumption of negligence in Article 103 of the Patent Act. This study is
unique in the following three points. First, this study found that the source book on which Article 103 of the
Patent Act is based is Section 59, subsection (1) of the Patents Act 1949 of the United Kingdom, and drew aconclusion that the content of negligence required under Article 103 of the Patent Act is the obligation to avoid
damages as the objective duty of care, that is, "having exercised due care so as not to work another person's
patented invention," and that Article 103 of the Patent Act also has the effect of playing a role as a code of
conduct on avoidance of damages for persons who work an invention. Secondly, based on discussions at theIndustrial Property Right System Reform Study Council and the opinions of persons who were involved in thelegislation of Article 103 of the Patent Act, this study found that Article 103 of the Patent Act was intended todesign a system in which expert opinions, bulletins, and Article 103 of the Patent Act operate as a trinity, anddrew a conclusion that bulletins and expert opinions play an important role in the proof of negligence in actual
lawsuits. Thirdly, this study saw the closeness of the role of experts' views (expert opinion) concerning negligencein the United States, Germany and Japan through comparison of court precedents and theories in the three
countries, which have different systems for remedy for patent infringement, and found certain suggestions
concerning the use of expert opinions in patent search practice.

I

Introduction

1

Purpose of This Study(2) Tangle of the Civil Code and Industrial
Property Right Law
The right to claim damages, which is designed
as a system as a remedy for right holders in cases
where an industrial property right has been
infringed, is based on Article 709 of the Civil Code.
Nonetheless, this has not always been so since theearliest days of patent law in Japan. The Patent
Monopoly Ordinance of 1885 had the basis of theright to claim damages as an independent right toclaim, and the Patent Ordinance of 1888 also
independently had the basis of the right to claim
damages.
On the other hand, the Civil Code was put inforce as a system of private person's rights, andArticle 709 of the Civil Code was designed. Alongwith that, Article 34 of the Patent Ordinance wasdeleted through the 1899 revision of the Patent
Ordinance, which established a system in which aright holder claims damages through application of(1) Raising Problems with Presumption of
Negligence under Industrial Property
Right Law
Article 103 of the Patent Act provides that "An
infringer of a patent right or exclusive license ofanother person is presumed negligent in thecommission of said act of infringement." Thepurpose of this provision is explained as shifting
the burden of proof from the right holder to aperson who works the invention. However, it canbe said that there are still no detailed studies onwhether Article 103 of the Patent Act applies toalmost all business operators, what the content ofnegligence provided for in Article 103 of the Patent
Act means, and whether Article 103 of the Patent
Act includes any problems.

(*) This is an English translation of the summary of the report published under the Industrial Property Research

Promotion Project FY2011 entrusted by the Japan Patent Office. IIP is entirely responsible for any errors in expression
or description of the translation. When any ambiguity is found in the English translation, the original Japanese text shallbe prevailing.

IIP Bulletin 2012 Vol.21●

1 ●Article 709 of the Civil Code if his/her patent rightis infringed. Thereby, a system was laid out inwhich the right to claim damages is generated
based on Article 709 of the Civil Code throughapplication of Article 709 of the Civil Code to allcases of infringement of a legally protected interest
called industrial property right. 1 Furthermore,
although the Patent Ordinance was revised in 1909,
the right to claim damages was not specially taken
into consideration within the framework of patentlaw. In addition, in the Taisho Era, the Old Patent
Act was enacted in 1921; however, the right toclaim damages was not specially taken into
consideration within the framework of patent law,and the system remained one in which the legal
requirements under Article 709 of the Civil Codeapply. However, Article 102 of the Patent Act(Presumption of Amount of Damage) and Article
103 of the Patent Act (Presumption of Negligence)
were created in 1959 as special provisions ofArticle 709 of the Civil Code.

actor's accusable malicious intent. Therefore,
scholars and courts made efforts to formulate
negligence again in order to correct the negative
effect of the fault liability principle. Example
theories include one suggesting that the obligation
to avoid damages to another person arises becauseof the existence of predictability and there is theobligation to predict the occurrence of damages aslong as there is predictability (according to thistheory, the obligation to avoid a result causing
damages does not arise if the party is unable topredict the occurrence of damages) and one
asserting that the obligation to avoid damages
arises without predictability. “Negligence,” inquestion in both of these theories, is the result ofheteronomous
evaluationoftheactor'sautonomous actions, specifically, violation of theobjective duty of care.
(5) Proof of Negligence
As requirements for the occurrence of theright to claim damages, Japanese tort law requiresthat (i) an infringer was intentional or negligent,that (ii) another person's right or legally protectedinterest was infringed by an infringer's intentionalor negligent act, and that (iii) infringement of aright or legally protected interest caused damages
to the infringed. In addition, as facts that support aright are supposed to be submitted by a person
who claims the right, if the plaintiff claims the rightto claim damages against the defendant, theplaintiff him/herself needs to present facts that
support his/her own right to claim damages asevidence. As a matter of course, the plaintiff must
prove facts that support his/her claim ofnegligence.2 Moreover, where the court is unable
to be assured of supporting facts in either apositive or negative way in court proceedings, thatis, where the existence of facts is unclear (nonliquet), the party who bears the burden of proof
will receive a legal determination disadvantageous
to him/herself in terms of the existence of the facts.
The issue of to which party the disadvantage
caused by the unclear existence of facts is
attributed is said to be the issue of the burden of
proof. Matters that are closely related to this issue
are legal presumption concerning proof of facts(this is a case where law provides that when fact B
that is easier to prove has been proven in proving
fact A that is subject to proof, it should berecognized that fact A has been proven without any
disproof. As provisions that include legal
presumption were designed to make it easy toprove facts that are subject to proof, fact B isordinarily a fact that is easier to prove than fact A.

(3) Attribution of Liability as a Requirement
for the Occurrence of Liability for
Damages
In terms of Japanese liability law, both Article
709 of the Civil Code and Article 415 of the Civil
Code require intention or negligence as arequirement for the occurrence of the right toclaim damages and adopt the fault liability principle.
The fault liability principle is the principle that
requires intention/negligence as a basis for theoccurrence of civil liability in terms of attributionof liability. Discussions concerning the fault liability
principle have changed along with social transition.
(4) Transition of the Theory of Negligence
under Liability Law
In modern society, liberalism, which is theidea of recognizing the greatest value in humanvoluntary actions, was embodied as the fault
liability principle within the framework of private
law. This is because a formula whereby an actor
does not have imposed any liability for damages incommitting any free acts unless he/she has any
accusable malicious intent could guarantee thefreedom of activity of the actor, secure thepredictability of damages, and realize prevention of
unexpected compensation. This led to more active
business activities and consequently contributed topromoting the development of capitalist society.
However, with rapid modernization andmass-production and mass-consumption, there
have been many cases in which the infringed
suffers damages despite the non-existence of the●

2 ●IIP Bulletin 2012 Vol.21

In the case of legal presumption, the defendantbears the burden of proof) and de facto presumption(De facto presumption means that where fact B has
been proven, the judge draws an inference that a
prima facie fact exists in conformity to the rule ofthumb within the scope of his/her free conviction.
In the case of de facto presumption, it is found thatfact A exists unless the other party blocks de facto
presumption by submitting a disproof. In this case,
it is not as if the principle of the burden of proof
has been changed by special law; therefore, theplaintiff bears the burden of proof in the case of defacto presumption). Legal presumption and de facto
presumption are the same in the point that where
there is a party who desires a certain legal effect tobe exerted, it is the other party to said party who
desires a certain legal effect to be exerted that
submits facts proving the legal requirements forexerting said legal effect. However, they differ incases where the existence of fact A has become
unclear as a result of submission of a disproof. Thatis, a person who suffers a disadvantage in cases
where the existence of fact A becomes unclear is aparty against whom exertion of a legal effect has
been asserted (defendant) in the case of legal
presumption while such a person is a party who
has asserted exertion of a legal effect (plaintiff) in
the case of de facto presumption.
On second thought, considering Article 103 of
the Patent Act mentioned at the beginning of thisreport, a person is presumed, pursuant to Article
103 of the Patent Act, to have been negligent inrelation to an act of infringement where he/she has
infringed another person's patent right. Therefore,
if a patentee or exclusive licensee proves the factof patent infringement when exercising the right toclaim damages based on the patent infringement, it
is legally presumed that a person who has worked
the invention was negligent. That is, said provision
is a provision on legal presumption. Therefore,
where a disproof is submitted, if the existence offacts concerning said Article is unclear, theinfringer of a patent right will suffer a disadvantage.
In this regard, it is necessary to ascertain the
negligence required under Article 103 of the PatentAct. This is because what duty of care an infringer
has fulfilled becomes the element of disproof
though presumption is reversed by submission of adisproof. Therefore, it can be said to be vital toascertain whether the negligence mentioned in
Article 103 of the Patent Act is an issue in terms of
the psychology of a person who worked theinvention (violation of subjective obligation), theobligation to avoid a result causing damages on thepremise of predictability (violation of the objective

IIP Bulletin 2012 Vol.21

duty of care), or a mere violation of the obligation
to avoid a result causing damages (violation of theobjective duty of care). In addition, in order tounderstand the way the court comprehends due
care that is necessary to reverse negligence in an
actual lawsuit, it is necessary to seek out based onwhat legal policy background legally protectedinterests, called patent rights, have become subject
to legal technical protection in the same manner as
integrity interests such as life and body.
Consequently, this study roughly covers thefollowing two issues.
2

Issues Covered by This Study(1) Relationships between Article 103 of the
Patent Act and the Duty of Care under
Substantive Law
Although it is said that Article 103 of the
Patent Act presumes negligence, one of the issuesof the study is to seek what the negligencepresumed there is.
(2) Relationships between Article 103 of the
Patent Act and the Burden of Proof under
Litigation Law
Article 103 of the Patent Act is said to be aprovision that shifts the burden of proof from aright holder to an infringer. One of the issues of thestudy is to seek what the legal policy perspective isthat exists behind the provision.
3

Consideration Method Adopted in ThisStudy

In order to solve the aforementioned two
issues and realize the purpose of this study, we
adopted a consideration method consists of thefollowing in this study: (1) considering thebackground of legislation through examination of
discussions at the Industrial Property Right
System Reform Study Council, reports of theIndustrial Property Right System Reform Study
Council, and discussions at the Diet in this order,(2) analyzing the generation and development oftheories and court precedents concerning
negligence of infringement of an industrial
property right before the 1959 Act in order to elicit
the meaning of Article 103 of the Patent Act, (3)analyzing the actual operation of Article 103 of the
Patent Act in court practice in relation to cases ofpatent infringement, considering the possibility of
indemnity and the scope of indemnity in cases ofpatent infringement and also conducting
comparative analysis of infringement cases in Japan,●

3 ●Germany and the United States, examining what
search obligation is required for indemnity or
lightening liability, and considering difference
between the handling of negligence and that ofexpert opinion, and (4) examining the patent
search obligation in consideration of the actual
conditions of articles of manufacture of current
technology-oriented companies and increase in useof patented products in the service industry.

defendant who proves that at the date of theinfringement he was not aware, and had noreasonable ground for supposing, that the patent
existed."Then, the draft modeled after the Patents Act
1949 of the United Kingdom was slightly modified
in terms of wording through deliberations, andbecame subject to discussion at the Third Meetingof the General Committee of the Industrial
Property Right System Reform Study Council7 as
the (draft) outline of the reform of general issues
concerning industrial property right law. 8 The
discussion revealed the following three points.
First, the wording, "presumed negligent," wascreated to make it possible to clearly understandthe shift of the burden of proof set forth in Section
59, subsection (1) of the Patents Act 1949 of theUnited Kingdom, which is the source book on
which the draft relied, from the wording of theprovisions of the revised Japanese law.9 Secondly,
it is possible to infer that, at the drafting stage, thedrafters had the idea that prima facie presumption
which is the result of accumulation of court
precedents before the 1959 Act and legal
presumption which is intended to be enacted into
law by the 1959 Act can be accepted without
awkwardness in practice as they are provisions
intended for the "same purpose," though theyrecognized that those presumptions were notentirely the "same."10 Thirdly, it appears that, fromthe drafting stage, the drafters questioned
requiring not manufacturers but users to exercise
the same degree of care pursuant to the relevant
provisions.11
Based on this discussion, the first draft of theoutline was modified. The (second draft) outline of
the reform of general issues concerning industrial
property right law was prepared in 1956,12 and it
was established as the draft outline of the reform ofgeneral issues concerning industrial property rightlaw (1).13 The outline became subject to discussion
at the Fifteenth Meeting of the General Committeeof the Industrial Property Right System Reform
Study Council. 14 The minutes of the meeting
revealed the following four points.
First,
thedrafters
understoodintention/negligence of patent infringement as theobligation to avoid the occurrence of damages frompatent infringement. 15 Secondly, the drafters
raised a problem concerning making prima facie
presumption, which had been made in practice incourt precedents before 1959, be "legal
presumption."16
Thirdly, the content of the negligence set forthin Article 103 of the Patent Act was maintained to

Ⅱ Legislative History of Article 103of the Patent Act
1

Deliberations at the Industrial Property
Right System Reform Study Council

In 1949, the Cabinet decided to establish acouncil designed to examine the industrial
property right system. It was decided to inaugurate
the Industrial Property Right System Reform
Study Council at a meeting of the Ministry ofInternational Trade and Industry in 1950, and theFirst General Meeting of the Industrial Property
Right System Reform Study Council was held. The
key points of civil liability-related issues in thereform were the issue of whether to include a
provisionconcerning
patentinfringement
independently in the Patent Act or as special law of
Article 709 of the Civil Code 3 and the issue
concerning correction of the fault liability
principle.4
In 1955, a draft revision bill of the Patent Act
was prepared under the heading of developing
substantive provisions on patent infringement. 5
The draft stated, regarding shift of the burden of
proof of subjective requirements, that, "if a person,
who runs a business in the field to which anotherperson's patented invention pertains, infringed thepatent right in running the business, he/she shallbe liable for restoration to the original statepursuant to (a); provided, however, that this shallnot apply when the person exercised due care so as
not to work the other person's patented invention."
Regarding said draft, the purpose of the draft was
explained at the 19th meeting of the Industrial
Property Right Law General Issue Reform Agency.
Specifically, it was explained that the draft was
prepared like this because "the infringer bears theburden of proof in any case in the United
Kingdom."6 This reveals that the source book on
which the drafters relied when preparing the draft
was the text of Section 59, subsection (1) of the
Patents Act 1949 of the United Kingdom,
specifically, "In proceedings for the infringement ofa patent damages shall not be awarded against a●

4 ●IIP Bulletin 2012 Vol.21

Bureau),26 the Fourth Reading at the Legal Affairs
Bureau, 27 and the Fifth Reading at the Legal
Affairs Bureau in 1959. 28 Consequently, theoriginal draft came to be a bill of the Patent Act tobe submitted to the Diet.

be "due care," which is the wording adopted at theinitial stage of the drafting.17 In the first place, inthe draft modeled after the Patents Act 1949 of theUnited Kingdom, the wording "presumed negligent
in the commission of the said act of infringement"
was adopted for clarity because Japan adopts thefault liability principle and a legal system design
whereby the right to claim damages that is a legal
effect cannot occur unless the requirement ofintention/negligence that is the legal requirement
set forth in Article 709 of the Civil Code is fulfilled.
There were no other discussions concerning thecontent of negligence. Taking these facts into
account, a formula, "having not exercised due careto avoid patent infringement = negligence," isestablished with regard to patent infringement.
Fourthly, since a person who works aninvention in patent infringement is liable fordamages unless he/she is able to prove that he/she
has exercised due care, it is obvious that a certain
standard was considered necessary to secure
predictability for persons who work inventions.18
In this deliberation, the point at issue was whatshould be used as this standard; however, thediscussion reached an agreement to use bulletinsas the standard.
After the aforementioned deliberations, a draft
report was submitted at the Second General
Meeting of the Industrial Property Right System
Reform Study Council. An explanatory leaflet on
the draft report stated that the revision of the
Patent Act in relation to liability law was prepared
as provisions designed to strengthen patentrights. 19 This draft report was subsequently
submitted to the Japan Patent Office as a report.20
2

3

The bill of the Patent Act was deliberated in
1959 at the 31st session of the Diet. In the
deliberations, it was confirmed that the provisions
on presumption of negligence exist as auxiliary
provisions of Article 709 of the Civil Code29 andare designed for remedy for the difficulty of proof
in patent infringement lawsuits.30 At the Diet, only
the purpose of legislation was confirmed, and noother special modification was made. The bill cameto be promulgated on April 13, 1959.
4

Summary of This Chapter

Article 103 of the current Patent Act was notdrafted through accumulation of court precedents
with the intention of prescribing de facto
presumption that had been recognized in court
precedents at the time of the old Act as legal
presumption but was drafted modeling after theprovisions on restriction on damages in the case ofpatent infringement, which were set in Section 59,
subsection (1) of the Patents Act 1949 of theUnited Kingdom. However, the wording of Article
103 was modified to some degree throughdeliberations at the General Committee, and thewording unique to Japan, "presumed negligent,"
was adopted. It is inferred that the backgroundbehind adopting this wording was the idea that as
Article 709 of the Japanese Civil Code provides
that "A person who has intentionally or negligently
infringed any right of others shall be liable tocompensateanydamagesresultinginconsequence," it is possible to make it easier for
people to clearly understand, under the Japanese
legal system whereby the basis of the right toclaim damages in the case of infringement of aright is placed in Article 709 of the Civil Code, that
Article 103 of the Patent Act is positioned as an
auxiliary law of Article 709 of the Civil Code, byadopting the wording, "presumed negligent in thecommission of the said act of infringement," rather
than the wording, "not supposed to be liable fordamages if he/she proves that he/she has exerciseddue care," when intending to reduce the burden of
proof of such intention/negligence.
Taking into account that the draft of Article
103 of the Patent Act was admitted in terms of the

Deliberations at the Reading at the Japan
Patent Office and at the Reading at theLegal Affairs Bureau

The first provisional draft on the Patent Act,
which had been made in 1956 by secretary Sueaki
Oda 21 , was brought to deliberations at the First
Reading at the Japan Patent Office in 1957.22 At theFirst Reading at the Japan Patent Office, no specialchange was made to the provisions on presumptionof negligence, and the issue was brought todeliberations at the Second Reading.23 Then, theoriginal draft that was modified and revised at theSecond Reading went through the Third Reading at
the Japan Patent Office (First Reading at the Legal
Affairs Bureau),24 the Fourth Reading at the Japan
Patent Office (Second Reading at the Legal Affairs
Bureau)25 in 1958, the Fifth Reading at the Japan
Patent Office (Third Reading at the Legal Affairs

IIP Bulletin 2012 Vol.21

Deliberations at the Diet●

5 ●

obligation based on bulletins.41

content of negligence which the defendant should
prove on the condition that bulletins are further
disseminated, it is clear that the due care includedin the wording "negligence" in Article 103 of the
Patent Act is one based on bulletins. That is, thecontent of negligence set forth in Article 103 of the
Patent Act is violation of the patent searchobligation on the premise of bulletins.

2

Taking into account that Mr. Aratama, who
was the manager of the time of the Legislative
Affiars Office (Office for deliberation of reform ofindustrial property right system) at the Japan
Patent Office, does not consider it impossible toimpose the patent search obligation on companies
which work inventions, it can be said that Article
103 of the Patent Act does not merely provide forshift of the burden of proof but also includes
creation of the patent search obligation undersubstantive law behind the provision of the burdenof proof under litigation law with the wording,"presumption of negligence."42 In addition, taking
into account that Mr. Aratama states that it ispossible to annihilate presumption of negligencebased on confidence in expert opinion, 43 it ispossible to infer that it was intended to design asystem in which bulletins, presumption of
negligence, and expert opinions work as a trinity asof the time of legislation of the 1959 Act.

Ⅲ Meaning of Article 103 of the
Patent Act
1

Understanding of Negligence Set Forthin Article 103 at the Time of Legislating
the 1959 Act

Status of the Theory of Negligence in
Court Precedents and Theories before
the 1959 Act

Court precedents before the 1959 Act shared
the view that negligence of an infringer was
non-exercise of care to matters publicly notified inpatent bulletins and the infringer is treated ashaving been negligent until he/she makes adisproof concerning the negligence31 and that an
infringer should prove the non-existence ofnegligence (the same view was adopted amongscholars 32 ) as it was clearly indicated thatnegligence of an infringer is prima facie
presumption.33
In court precedents, the content of the duty ofcare was understood as search of bulletins. 34 In
addition, as the court also required voluntarily
questioning orderers and conducting othervoluntary searches in the case of manufacturing ofproducts upon commission from other persons,35 it
seems that the court imposed the obligation tovoluntarily conduct patent search on persons who
work inventions. Scholars were also consistent
with the court from the era of the old Act in thatnegligence means non-fulfillment of the patent
search obligation.36
In court precedents, the following cases havebeen regarded as reasons for proving thenon-existence of negligence of a person who works
an invention: where the invention turned out to be
publicly known as a result of fulfillment of thepatent search obligation,37 where it turned out tobe difficult even for a trial examiner to determine
validity/invalidity as a result of fulfillment of thepatent search obligation,38 where the right holder
has not worked the invention after the right was
registered,39 and where it turned out to be difficult
to determine whether working of the invention
falls within the scope of the right as a result offulfillment of the search obligation. 40 Scholars
were consistent with the court in that negligencemeans non-fulfillment of the patent search3

Summary of This Chapter

The substantive meaning of Article 103 of the
Patent Act is to have created the objective duty ofcare by including the objective duty of care in thewording, "presumption of negligence." The content
of Article 103 is the patent search obligation basedon bulletins. That is, it can be said that the bases of
attribution of liability to a person who works aninvention are the fact that the person has come toinfringe another person's right due to no conduct ofpatent search despite the existence of informationon the right of the right holder that can be readfrom a bulletin and the fact that the person has notcommitted any act to avoid damages though he/she
has read information on the right of a right holder
from a bulletin through fulfillment of the patent
search obligation. From this, it is possible to see
the role of Article 103 of the Patent Act as a code of
conduct on avoidance of damages to prevent acts of
infringing patentees' patent rights.
In addition, Article 103 of the Patent Act
is a legal provision that defines fulfillment of thepatent search obligation based on bulletins as
payment of the duty of due care and requires aperson who works an invention (the infringer) toprove that he/she has exercised said duty of due
care, with the aim of strengthening industrial●

6 ●IIP Bulletin 2012 Vol.21

property rights. For sure, Article 103 of the Patent
Act lightened patentees' burden of proof in order tostrengthen industrial property rights, and in thatsense, it leads to a consequence of protecting rightholders without fail. However, taking into accountthat the scope of patentees' rights is published tothe public in the form of a bulletin, Article 103 of
the Patent Act can be understood as legislation that
does not lead to a consequence of giving advantage
unilaterally to right holders.44 In addition, taking
into account that the patent system is to grant an
exclusive right, that is, patent right, to a person
who has published new technology for a certain
period under certain conditions in return for the
publication, to give third parties an opportunity to
use the published invention, and to contribute to
the development of industry by promoting advancein technology while seeking harmony between
those who have been granted rights and use by
third parties subject to restrictions by those rights,
the shift of the burden of proof under Article 103 of
the Patent Act not only contributes tostrengthening patentees' rights but also can be said
to function to realize mutual respect of the rights ofright holders and those of persons who work
inventions. In other words, a person who works aninvention with a license granted by a patentee issubject to restriction on freedom of action thatprevents infringement of another person's right byan agreement in the form of granting of anon-exclusive license under Article 78 of the
Patent Act, and a person who works an invention
without a license granted by a patentee is subject
to restriction on freedom of action that prevents
infringement of another person's right by tort in
the form of the shift of the burden of proof under
Article 103.

protect their own rights by themselves because
negligence is not presumed for infringement ofrights during the period from the registration of
establishment of rights to the issuance of such a
publication. For example, right holders take suchmeasures as active notification of the existence ofrights to persons who work inventions. Where any
person continues to work an invention even after
receiving a notification from a right holder, theperson's
negligenceisfound;
therefore,
compensation for damages to the right holder isreckoned from the time of registration of
establishment of the patent right.46(2) Issue of Due Care
It is possible to analyze court precedents inJapan separately from the perspective of (i)experts' opinions and due care, (ii) not having
conducted search and due care, (iii) cases where
search has been completed before another person
obtains a right and due care, (iv) cases where thedescription originally attached to the application
was corrected and due care, (v) indication of apatent and due care, (vi) conflict and due care, (vii)
succession of business and due care, (viii)
specialized skills and due care, and (ix) types ofbusiness other than manufacturing business anddue care. The idea common to these court
precedents is "whether a person who works aninvention has fulfilled the search obligation throughbulletins." Nonetheless, if duty of care equivalent
to that imposed on manufacturers is imposed on
persons who work inventions, irrespective ofwhether the persons have specialized skills or are
retail stores, they have no other choice but to rely
on expert opinion, and requesting expert opinion
becomes an essential patent search practice.
However, regarding whether such persons are
deemed to have fully exercised due care in Japanby following such experts' opinions, court
precedents indicate that merely following experts'
opinions is not regarded as having fulfilled the dutyof care.47 In addition, even where there are two or
more expert opinions, presumption is not reversed
through mere confidence in the expert opinions.48
Moreover, presumption is also not reversed
through mere confidence in an expert opinion of aperson other than a patent attorney who filed therelevant application. 49 In this regard, carefully
reading the holdings of the court, it is importantthat the court held that "mere" hearing andfollowing experts' opinions is not sufficient toreverse presumption of negligence. That is, it canbe said that the court states that persons who work
inventions are not exempted from the duty of care

Ⅳ Possibility of Indemnity in Patent
Infringement Cases
1

Possibility of Indemnity in
Infringement Cases in Japan

Patent(1) Issue of Starting Point of Reckoning
As Article 103 of the Japanese Patent Act
provides that negligence shall be presumed, thestarting point of reckoning of this presumption of
negligence becomes an issue. According to court
precedents, the time of issuance of a publication ofan examined patent application is regarded as thestarting point of reckoning.45 Therefore, the timeof occurrence of the right to claim damages is also
after the issuance of such a publication. In that case,right holders likely need to take measures to

IIP Bulletin 2012 Vol.21●

7 ●by entrusting experts with search and requires
such persons to determine whether their own acts
constitute infringement of a right by themselves byconducting search by themselves.
2(2) United States
In the United States, a right holder can, when
his/her patent is infringed, claim compensation fordamages to him/herself against the infringer in thesame manner as in Japan and Germany. However,court precedents concerning patent infringementsin the United States regard patent infringement as
being subject to strict liability.53 Therefore, it is
not necessary for right holders to prove
intention/negligence of an actor. The United States
differs from Japan and Germany in this regard.
In the United States, intention/negligence
does not matter in the theory of infringement but it
matters only at the stage of the theory of damages.
Treble damages are awarded in cases where theplaintiff is intentional. 54 Determination of"intention," which is definitive information formaking a decision to award treble damages, isclosely related to experts' opinions (expert
opinion) in the United States.55 Then, in order toavoid treble damages in cases where a person
asked a lawyer for legal advice and followed theadvice but resulted in infringing another person's
patent right, that is, where a person infringed aright as a result of following the opinions of acertain expert, it is necessary to fulfill thefollowing three requirements, (i) appropriate time,(ii) appropriate qualification, and (iii) appropriate
opinion. If a person followed the opinions of alawyer that fulfill these requirements, theinfringement is deemed to be negligent
infringement and he/she only needs to compensate
actual damages.56

Possibility of Indemnity in Patent
Infringement Cases in Other Countries(1) Germany
In Germany, a right holder can, when his/herpatent is infringed, claim compensation fordamages to him/herself against the infringer in thesamemannerasinJapan.
Then,
intention/negligence of a person who works aninvention is necessary for the occurrence of theright to claim damages, and the fault liability
principle is adopted in Germany just like Japan.
Negligence in patent infringement in Germany
is perceived to be (1) the state where a person
does not exercise the reasonable care that isrequired in transactions (negligence mentioned in
Section 276 of the German Civil Code (Fahrlässig
handelt, wer die im Verkehr erforderliche Sorgfalt
außer Acht lässt. (A person acts negligently if hefails to exercise reasonable care))), (2) error(Irrtum), and (3) good faith (Unkenntnis). 50
Exercising the care that is required in transactions
when handling patent rights means conducting
search of other persons' patents, and not having
conducted search of other persons' patents thus
naturally means negligence. In addition, cases
where a person conducted search of other persons'patents but thought that the working is outside thescope of those other persons' patent rights andcases where a person conducted search of otherpersons' patents but did not become aware of theexistence of other persons' rights also fall under
negligence in Germany. In this point, Germany has
a tendency similar to Japan.
The next issue is the issue of proof of legal
requirements, intention/negligence. In Germany,
there are no legal provisions to the effect thatnegligence is presumed, like those in Japan.
However, if a right holder proves the fact of patent
infringement, negligence of the person who works
the invention is prima facie presumed.51
In Germany, where a person who works aninvention has obtained an expert opinion
advantageous to him/herself, if he/she infringes
another person's patent right as a result of his/her
confidence in the expert opinion, he/she is unable
to be exempted from the liability for damages forthe reason of obtainment of the expert opinion.52
This reveals that Germany has a tendency similar
to Japan in this regard.

3

Summary of This Chapter

Comparing systems relating to negligence inpatent infringement in Japan, Germany and theUnited States, Japan and Germany adopt
negligence liability while the United States adopts
strict liability. This reveals that Japan/Germany andthe United States adopt systems that totally differ
in terms of whether the attribution of liability isrequired as the basis of compensation for damages.
Furthermore, comparing Japan and Germany,both of which are countries that adopt negligenceliability, Japan adopts legal presumption under
Article 103 of the Patent Act while Germany
adopts prima facie presumption. These countries
adopt different systems in terms of proof of
negligence. However, in actual proof, both
Germany and Japan appear to result in drawing
similar conclusions with regard to the method of
adopting experts' opinions.
●

8 ●IIP Bulletin 2012 Vol.21

In Japan, Germany and the United States,
hearing opinions from experts in patent search is avery important patent search practice. In Japan andGermany, even where a person has worked apatented invention as a result of following anexpert's opinion, it does not prove thenon-existence of negligence. Therefore, liability fordamages arises as negligence liability. On the other
hand, in the United States, where a person has
worked a patented invention as a result of following
an expert's opinion, if the opinion is of an expert
who fulfills certain requirements, the person does
not bear liability for intentional damages. That is,liability for negligent damages arises. In this regard,
it can be said that all three countries lead to similar
conclusions.
In carrying forward global development
utilizing intellectual property rights, an actor'sability to utilize experts' opinions well appears tocontribute to avoiding and reducing compensation
for damages concerning intellectual property
infringement.

expert with patent search and infringed anotherperson's right as a result of working an invention
on the faith of the results of the search, the factthat the person entrusted the search does not
become a reason for indemnity from liability fordamages. At the time of legislation, Article 103 of
the Patent Act was designed based on the idea thathaving given confidence to an expert opinion
becomes a reason for indemnity; however, in reality,
it does not become a reason for indemnity. It is
probably necessary to reconsider whether asystem design in which fulfillment of the patent
search obligation concerning intention/negligence
becomes a reason for indemnity is correct undersuch actual conditions.

Ⅵ Conclusion
The following issues can be extracted fromthe gap between Article 103 of the Patent Act andthe actual conditions of patent search practice.
The first issue is whether it is appropriate tomaintain the composition of the provision,"presumed negligent," which was assumed basedon the technical level of the time of the 1959 Act,taking into account the actual conditions of
products
manufactured
bycurrenttechnology-oriented companies and changes in the
production manufacturing process caused by thetransition of manufacturing business.
The second issue is whether there is muchpoint in continuing to maintain wording that is rarein terms of comparative law in the text of the
Patent Act in the situation where the wording of
Article 103 of the Patent Act substantially includes
the "patent search obligation" on companies while
the court determines the existence of negligencewith respect to each case in practice.
The third issue is whether to impose thesearch obligation to the same degree as that
imposed on manufacturing businesses onretail/distribution businesses, taking into accountthe current situation of patented products, that is,multiple patents are used for one product, as wellas the current situation of prosperity of service
businesses under technical innovation.
As the fourth issue, though the basis of defacto presumption of negligence and the theory ofabsolute liability that has been formed in civil law
study under the fault liability principle in Japan was
the respect of legally protected interests, that is,life and body, which should be protected even bymodifying the fault liability principle, it isnecessary to reconsider whether industrial
property rights are legally protected interests thatⅤ Patent Search Practice andContemporary Meaning of Article
103
It is said that, in recent years, many patents
have been involved in the process of research anddevelopment, manufacturing, and sale of one
product and thereby, "patent thickets" have been
formed. In that case, persons who work inventions
have to conduct search of all patents in patent
thickets so as to confirm whether they do not
infringe any other person's right. Moreover, under
Article 103 of the current Patent Act, both large
companies and small and medium-sized companies
are imposed with the same search obligation,
irrespective of business scale, and the same degreeof search obligation is imposed irrespective ofwhether companies have expert knowledge.
Therefore, small and medium-sized companies also
have to conduct detailed patent search of the same
degree as large companies. It is necessary toreconsider whether small and medium-sizedcompanies are actually able to fully conduct searchof hundreds and thousands of patents at all stagesof planning, development, manufacturing, and sale.
Article 103 of the current Patent Act requires
both manufacturers and retailers to fulfill thepatent search obligation to the same degree. In thatsense, in patent search, more importance will be
attached to entrustment of patent search toexperts in the future without fail. However, as
overviewed above, where a person entrusted an

IIP Bulletin 2012 Vol.21●

9 ●can be on par with said legally protected interests.
Is it necessary to artificially establish national
policy legislation under the necessity ofstrengthening rights for the development ofindustry because industrial property rights are notlegally protected interests that can be on par withsaid legally protected interests? There is an issueof whether it is necessary to reconsider the ideathat underlies presumption of negligence.
1

2

3

4
5

6

7

8

With regard to placing the basis of the right to claim
damages in the case of a patent infringement on Article
709 of the Civil Code, Professor Nakayama states that,"In terms of the theory of legislation, it is also a possible
method to establish a provision permitting a claim fordamages in the Patent Act. However, in practice, it
seems unlikely that patent infringement does not fallunder tort. Therefore, whether to establish a provision
on compensation for damages in the Patent Act does notcause any difference in the result, and it is nothing morethan an issue of technique of legislation." Thereby, hebases patent infringement on infringement of a right set
forth in Article 709 of the Civil Code and does not denyrecognizing the Civil Code as the basis of theoccurrence of the right to claim damages (Nobuhiro
Nakayama, Tokkyoho (Patent Act) (Koubundou, 2010),
335).
Judgment of the Supreme Court of Judicature ofJapanese Empire, March 24, 1915 (Minroku, 21st series,
at 412); the following are court precedents to the same
effect: judgment of the Supreme Court of Judicature ofJapanese Empire, September 22, 1903 (Minroku, 9thseries, at 989), judgment of the Supreme Court of
Judicature of Japanese Empire, May 8, 1905 (Minroku,
11th series, at 629), judgment of the Supreme Court of
Judicature of Japanese Empire, June 19, 1903 (Minroku,
11th series, at 992), judgment of the Supreme Court of
Judicature of Japanese Empire, April 27, 1909 (Minroku,
15th series, at 396), judgment of the Supreme Court of
Judicature of Japanese Empire, November 15, 1913
(Minroku, 19th series, at 956), judgment of theSupreme Court of Judicature of Japanese Empire, March
13, 1919 (Minroku, 25th series, at 428), judgment of theSupreme Court of Judicature of Japanese Empire, April8, 1920 (Minroku, 26th series, at 482), judgment of theSupreme Court of Judicature of Japanese Empire, April
12, 1920 (Minroku, 26th series, at 527), and judgment of
the Supreme Court of Judicature of Japanese Empire,
September 12, 1930 (Shimbun, No. 3177, at 14).
Contained in Industrial Property Right System Reform
Study Council, General Affairs Department, Japan
Patent Office, "Kogyoshoyukenseidokaisei ni kansuru
sochijiko (Measures concerning the reform of theindustrial property right system)."
Id.
Industrial Property Right Reference Material Center,"Tokkyobukai ippanbukai kankei genan sakusei siryo(Materials for preparing original plans used by the
Patent Committee and the General Committee)"(Aratama Bunko 28).
Industrial Property Right Reference Material Center,"Kogyoshoyukenshingai ni kansuru kaisei siryo

●

9
10
11
12

13
14
15
16
17
18
19

20
21

22
23
24

25

26
27
28
29

(Materials for reform concerning infringement ofindustrial property rights)" (Aratama Bunko 29).
Industrial Property Right Reference Material Center,"Kogyoshoyukenseidokaiseishingikai ippanbukai
gijiyoroku (Minutes of the General Committee of theIndustrial Property Right System Reform Study
Council)" (Aratama Bunko 27).
"A person who runs a business in the field to whichanother person's patented invention pertains bears theliability set forth in (a) for infringement of the patentright he/she has committed in running the business;
however, if he/she proves that he/she has exercised due
care so as not to work the other person's patented
invention, he/she shall not be liable for the
infringement" (Id.).
Id.
Id.
Id.
Industrial Property Right Reference Material Center,"Kogyoshoyukenshingai ni kansuru kaisei siryo(Materials for reform concerning infringement ofindustrial property rights)" (Aratama Bunko 29).
Id.
Id.
Id.
Id.
Id.
Id.
Industrial Property Right Reference Material Center,"Toshin kaisei kogyoshoyuken hoshu (Report: collectionof revised industrial property right laws)"(Aratama
Bunko 15).
Id.
First provisional draft of August 4, 1956:
Article 170 (Presumption of Negligence), "If a business
operator infringes another person's patent right or
exclusive license in production, use, sale, putting into
distribution, or import within the scope of his/her own
business, he/she is presumed to have been negligent inrelation to the infringement" (Industrial Property Right
Reference Material Center, "Tokkyohoan (tokkyocho
nai shingi yo) (Bill of the Patent Act (for deliberations
within the Japan Patent Office))," Aratama Bunko 14).
Id.
Id.
Industrial Property Right Reference Material Center,"Tokkyohoan (hoseikyoku daiichidokkai yo) showa 32
nen 8 gatsu 16 nichi – showa 33 nen 1 gatsu 8 nichi (Billof the Patent Act (for the First Reading at the Legal
Affairs Bureau) for the period from August 16, 1957, toJanuary 8, 1958)" (Aratama Bunko 16).
Industrial Property Right Reference Material Center,"Tokkyohoan (hoseikyoku dainidokkai iko no bun)showa 33 nen 1 gatsu 13 nichi – showa 34 nen 1 gatsu
12 nichi (Bill of the Patent Act (for the Second andsubsequent Readings at the Legal Affairs Bureau) forthe period from January 13,1958, to January 12, 1959)"(Aratama Bunko 17).
Id.
Id.
Id.
Minutes of the meeting of the Committee on Commerceand Industry of the House of Councillors at the 31st
session of the Diet, No. 7, at 2.

10 ●IIP Bulletin 2012 Vol.21

30

31

32

33

34

35

36
37

38

39

40

41
42

43
44

45

46

Minutes of the meeting of the Committee on Commerceand Industry of the House of Councillors at the 31st
session of the Diet, No. 12, at 6.
Judgment of the Supreme Court of Judicature ofJapanese Empire, May 9, 1905 (Keiroku, 11th series, at
490).
Ichiro Kiyose, Tokkyoho genri (Principle of the Patent
Act) (Ganshodo, 1936), 158; Kakuji Takeuchi, Tokkyoho(Patent Act) (Ganshodo, 1938), 337; Hane Izuka,
Mutaizaisanho (Intangible property law) (Gansho do,1940), 173; Izutaro Suehiro, Kogyoshoyukenho(Industrial property right law) (Nippon Hyoron Sha,
1942), 60; Kikushiro Nagata, Kogyoshoyukenron(Industrial property right theory) (Fuzambo, 1959), 301.
Judgment of the Supreme Court of Judicature ofJapanese Empire, June 16, 1915 (Keiroku, 21st series,
at 822).
Judgment of the Supreme Court of Judicature ofJapanese Empire, March 11, 1904 (Minroku, 10th series,
at 255); judgment of the Supreme Court of Judicature ofJapanese Empire, October 25, 1907 (Keiroku, 13thseries, at 1194); judgment of the Supreme Court of
Judicature of Japanese Empire, October 4, 1910
(Keiroku, 16th series, at 1599); and judgment of theSupreme Court of Judicature of Japanese Empire, June
16, 1915 (Keiroku, 21st series, at 822).
Judgment of the Osaka Court of Appeal, September 25,
1936 (Horitsushimbun No. 4050, at 15).
Kiyose, supra note 34 and Nagata, supra note 34.
Judgment of the Supreme Court of Judicature ofJapanese Empire, October 4, 1910 (Keiroku, 16th series,
at 1599).
Judgment of the Tokyo Court of Appeal, October 25,
1912 (Horitsushimbun, No. 828, at 21).
Judgment of the Tokyo District Court, March 30, 1940
(Horitsushimbun, No. 4561, at 3).
Judgment of the Tokyo Court of Appeal, July 13, 1942
(Horitsushimbun, No. 4810, at 15).
Kiyose, supra note 34 and Nagata, supra note 34.
Yoshito Aratama, "Kogyoshoyukenseidokaiseishingikai
toshin ni tsuite (san)" (Regarding the report of theIndustrial Property Right System Reform Study Council(3)), Zaikeishoho, vol. 94: 573.
Id.
In this regard, Professor Doi states that, "Presumptionof negligence under Article 103 cannot be said to be
attaching too much importance to protection of rightholders, taking into account public notice and theregistration system," thereby suggesting that Article
103 of the Patent Act does not merely exert effectattaching too much importance to protection of rightholders. On this point, he has a similar view to theauthor. (Teruo Doi, Chitekishoyukenho (Intellectual
property right law) (Seirin Shoin, 1982), 123).
Judgment of the Osaka District Court, March 29, 1972
(Road safety bar case) (Hanta, No. 278, at 263);
judgment of the Osaka District Court, November 28,
1973 (Duster shaft case) (Hanta, No. 308, at 278);
judgment of the Osaka High Court, May 27, 1994
(Clamp case); judgment of the Osaka District Court,
July 26, 2001 (Wallpaper paste machine case); andjudgment of the Tokyo District Court, July 16, 2010
(Silber Villa case).
Judgment of the Osaka District Court, July 26, 2004

IIP Bulletin 2012 Vol.21

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47

48

49

50

51

52

53

54

55

56

(Shelf case).
Judgment of the Tokyo District Court, September 21,
1963 (Vinyl can case) (Hanta, No. 152, at 177); andjudgment of the Tokyo District Court, June 26, 1972
(Desk lamp case) (Hanta, No. 282, at 267).
Judgment of the Tokyo District Court, April 25, 2002
(Foreign matter separating and removing apparatus for
raw laver case).
Judgment of the Osaka District Court, October 30, 1984
(Carrier bag handle case) (Hanta, No. 543, at 263);
judgment of the Osaka District Court, August 30, 1989
(Dry mount press case) (Tokkyo to Kigyo, No. 250, at66); and judgment of the Tokyo District Court, August30, 1993 (Aderans case) (Tokkyocho Koho, No. 38, at
328).
Georg Benkard, Patentgesetz Gebrauchsmustergetz,
9.,neubearbeitete Auflage, 1993, S.1269(Rüdiger
Rogge).
Urteil des Bundesgerichtshofs von 3. Juni 1976,Aktz: X
ZR 57/73,(GRUR 1976 579)). Another court precedent
to the same effect is Urteil des Bundesgerichtshofs vom
19. Dezember 1958, Aktz: X ZR 138/57 (GRUR 1959
478).
Urteil des Bundesgerichtshofs vom 19. Dezember
1958,Aktz: X ZR 138/57,(GRUR 1959 478). Other court
precedents to the same effect are Urteil desBundesgerichtshofs vom 19, Dizember 1950 Aktz: I ZR
62/50(GRUR1951
159)
and
UrteildesBundesgerichtshofs vom 30 Oktober 1956 Aktz: I ZR
199/ 55(GRUR 1957 342).
Thurber Corp. v. Fairchild Motor Corp.269 F. 2d 841;
Hilton Davis Chemical Co. v. Warner-Jenkinson
Co.,Inc.62 F.3d 1512; Warner-Jenkinson Co., Inc. v.
Hilton Davis Chemical Co.117 S. Ct. 1040; In re Seagate
Tech., 497 F. 3d 1360.
Beatrice Foods Co. v. New England Printing &Lithographing Co.,923 F.2d 1576.
Donald S. Chisum, Amerika tokkyoho to sono tetuzuki(Elements of United States Patent Law) (Yushodo Press,
2000), 629.
Id. at 637.

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