=================================================================
Date of the judgment (decision)–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

2011.12.19=================================================================
Case Number–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

2009 (A) 1900=================================================================
Reporter–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Keishu Vol. 65, No. 9=================================================================
Title–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Decision concerning the case in which the accused was prosecuted for accessoryship toviolation of the Copyright Act on the grounds that he released a file-sharing software
program called Winny, which can be used both for legitimate purposes and for the
purpose of infringing copyrights, and provided it to many and unspecified persons via
the Internet, thereby aiding the principals in infringing the authors' right to effectpublic transmission of their works, with the use of said software program; the court
determined that the accused lacked the intent of accessoryship=================================================================
Case name–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

1 / 29Case charged for accessoryship to violation of the Copyright Act=================================================================
Result–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Decision of the Third Petty Bench, dismissed=================================================================
Court of the Second Instance–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Osaka High Court, Judgment of October 8, 2009=================================================================
Summary of the judgment (decision)–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––In the case where the accused was prosecuted for accessoryship to violation of the
Copyright Act on the grounds that he released a file-sharing software program called
Winny, which can be used both for legitimate purposes and for the purpose of
infringing copyrights, and provided it to many and unspecified persons via the Internet,
thereby aiding the principals in infringing the authors' right to effect public
transmission of their works, with the use of said software program, given the facts ofthe case (as described in the text of the decision), namely, (i) it is obvious that theaccused did not release and provide Winny while perceiving or accepting a specific andimmediate risk of copyright infringement to be committed with the use of it, and (ii)upon releasing and providing Winny, the accused always warned users not to use
Winny for the purpose of infringing copyrights, it is difficult to go so far as to find thatthe accused perceived or accepted a high probability that a wide range of persons
would use Winny for the purpose of infringing copyrights to a level where their use
2 / 29cannot be tolerated as exceptional, so the accused lacked the intent of accessoryship tothe crime of violation of the Copyright Act.
(There is a dissenting opinion.)=================================================================
References–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Article 62, paragraph (1) of the Penal Code, Article 23, paragraph (1) and Article 119,
item (i) of the Copyright Act (prior to the revision by Act No. 92 of 2004)

Article 62, paragraph (1) of the Penal Code
A person who aids a principal is a accessory.

Article 23, paragraph (1) of the Copyright Act (prior to the revision by Act No. 92 of
2004)
The author shall have the exclusive right to effect a public transmission of his/herwork (including, in the case of automatic public transmission, making his/her worktransmittable).

Article 119, item (i) of the Copyright Act (prior to the revision by Act No. 92 of 2004)
A person who falls under any of the following items shall be punished by imprisonment
with work for not more than three years or a fine of not more than three million yen:(i) a person who infringes on the moral rights of author, copyright, right of publication,
moral rights of performer or neighboring rights (excluding a person who reproduces byhim/herself a work or performance, etc. for private use purposes as provided for in
Article 30, paragraph (1) (including the cases where applied mutatis mutandis
3 / 29pursuant to Article 102, paragraph (1)), and a person who, pursuant to the provisionsof Article 113, paragraph (3), commits an act deemed to constitute an act of
infringement on the moral rights of author, copyright, moral rights of performer orneighboring rights (including rights deemed to constitute neighboring rights pursuant
to the provisions of Article 113, paragraph (4); the same shall apply in Article 120-2,
item (iii))).
=================================================================
Main text of the judgment (decision)–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

The final appeal is dismissed.
=================================================================
Reasons–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Among the reasons for final appeal argued by the public prosecutor, the reason alleging
violation of judicial precedent is irrelevant in this case because the cited judicial
precedent addresses a different type of facts, and the rest are assertions of errors infact finding or unappealable violation of laws and regulations, and none of thesereasons can be regarded as a reason for final appeal permissible under Article 405 of
the Code of Criminal Procedure.
Having examined the arguments, however, we make a determination by this court’s
own authority with regard to whether or not the act of the accused to release thefile-sharing software program in question and to provide it to many and unspecified
persons constitutes accessoryship to the crime of violation of the Copyright Act.
Although the judgment in prior instance erred in construing the laws and regulations
relating to the constituent elements of accessoryship, we can affirm it as justifiable in
4 / 29terms of its conclusion that the act of the accused does not constitute accessoryship tothe crime of violation of the Copyright Act. The reasons for our conclusion are as
follows.
1. The accused developed a file-sharing software program called Winny, and releasedon the Internet its upgraded versions successively and provided them to many andunspecified persons via the Internet. Two persons were prosecuted as the principals forcommitting violation of the Copyright Act by using this software program and making
the data of videogame software programs, etc., which are categorized as copyrighted
works, automatically transmittable to the public or Internet users, thereby infringing
the authors' right to effect public transmission of their works (Article 23, paragraph (1)of the Copyright Act), and accordingly, the accused was prosecuted on the grounds thatwhat he had done prior to the principals' commission of the crime, that is, releasing
and providing the latest versions of Winny, constitutes accessoryship to the crime ofviolation of the Copyright Act committed by the principals. According to the findings by
the judgment in prior instance as well as the case records, the following facts can befound.
(1) Winny is a file-sharing software program that functions to send and receive datawith the applied use of peer-to-peer (P2P) technology by which a network of computers
is formed in a manner that individual computers act equally, with no central server
involved. It is equipped with the function to secure anonymity of the sender(anonymity function), as well as with various functions for searching for files and forsending and receiving file data efficiently, such as the clustering function, multiple
downloading function, and automatic downloading function. It can be applied invarious fields as it makes it possible to perform the exchange of a variety of data
efficiently while maintaining secrecy of communications. However, it can also be used
5 / 29in a manner that infringes copyrights, as it was done by the principals of this case.
(2) With the goal of technically verifying whether a new file-sharing software program,which ensures both anonymity and efficiency, would be actually operable, the accusedlaunched the development of Winny on April 1, 2002, and released the first trial
version of Winny on May 6, 2002, on the website that he had established. The accused
subsequently released the upgraded versions of Winny successively, and on December
30, 2002, he released Winny 1.00, the official version of Winny, and then Winny 1.14 on
April 5, 2003, at which point he put an end to the development of Winny as afile-sharing software program (Winny 1). After that, with the goal this time of
implementing a large-scale bulletin board system (BBS) using P2P technology, on April
9, 2003, the accused launched the development of Winny 2 as a software program
designed for this goal. On May 5, 2003, he released the first trial version of Winny 2,
and in September 2003, he released other versions of Winny successively, Winny2.0β6.47 and Winny 2.0β6.6, which were used by the two principals of this case(hereinafter collectively referred to as the "Alleged Versions of Winny"). Although
Winny 2 was developed with the goal of implementing a large-scale BBS as mentioned
above, it also had almost the same functions as Winny 1 as a file-sharing software
program (hereinafter Winny 1 and Winny 2 shall collectively be referred to as "Winny").
Upon releasing Winny, the accused posted a cautionary message on his website, stating"Do not exchange illegal files with the use of these software programs."(3) B, one of the principals of this case, around September 3, 2003, downloaded andacquired Winny 2.0β6.47 that had been released by the accused, and although B was
not eligible for any statutory exceptions, nor did he obtain authorization from theauthors, from September 11 to 12, at his residence, using a computer connected to thehard disk that stored the data of 25 titles of video game software programs, which are
6 / 29categorized as computer program works, and maintaining the computer connected to
the Internet, B started up said version of Winny on which said data were contained ina specific folder and ready to be uploaded, and made the data automaticallytransmittable to many and unspecified Internet users who would access said computer,thereby infringing the authors' right to effect public transmission of their works inviolation of the Copyright Act. C, another principal of this case, around September 13,
2003, downloaded and acquired Winny 2.0β6.6 that had been released by the accused,
and although C was not eligible for any statutory exceptions, nor did he obtain
authorization from the authors, from September 24 to 25, at his residence, using acomputer connected to the hard disk that stored the data of two titles ofcinematographic works, and maintaining the computer connected to the Internet, Cstarted up said version of Winny on which said data were contained in a specific folder
and ready to be uploaded, and made the data automatically transmittable to many andunspecified Internet users who would access said computer, thereby infringing theauthors' right to effect public transmission of their works in violation of the CopyrightAct.
2. The court in first instance stated that the technology involved in Winny is itself
value-neutral and it is inappropriate to stretch the scope of accessoryship with no limit,
to the extent that any act of providing such value-neutral technology would be
criminalized, and held that whether or not it is unlawful to provide such technology toothers, in the end, depends on the actual situation of the use of the technology insociety and the provider's perception of such situation, and also on the provider'ssubjective views upon provision. Based on this reasoning, the court of first instancedetermined that in the circumstances where most of the files exchanged on theInternet using Winny and other file-sharing software programs were eligible for7 / 29copyright protection, such file-sharing software programs including Winny were used
in a manner that infringes copyrights, and among them, Winny was recognized insociety as a software program that kept users safe from the risk of being captured for
copyright infringement and was widely used due to its efficiency and convenientfunctions. The court then found that the accused, while knowing the actual situation of
the use of file-sharing software programs, and Winny in particular, and expecting a
new business model to be created with the use of Winny and accepting such way ofusing it, released the Alleged Versions of Winny on the website that he had establishedso as to make them available to many and unspecified persons, and this led theprincipals to commit the charged crime. In conclusion, the court of first instancedetermined that the act of the accused can be regarded as constituting accessoryshipand found the accused guilty of accessoryship to the crime of violation of the CopyrightAct, and rendered a judgment sentencing the accused to a fine of 1.5 million yen.
3. Against the judgment in first instance, the public prosecutor appealed by reason of
inappropriate sentencing, and the accused also appealed by reason of violation ofprocedural laws and regulations, errors in fact finding, and errors in the application oflaws and regulations. With regard to the allegation of errors in the application of laws
and regulations concerning the establishment of accessoryship, the court of priorinstance held that accessoryship to be established by means of the act of providing asoftware program on the Internet is a new type of accessoryship that has never been
seen before, so it is necessary to carefully deliberate on whether or not to impose
criminal penalty on this type of accessoryship, from the perspective of the principle oflegality. The court then stated as follows: "In order to prove that the act of providing avalue-neutral software program on the Internet has made it easy for the principal tocommit the criminal act, it is not sufficient that the provider of the software program
8 / 29perceives and accepts the possibility or probability that someone among many andunspecified persons would engage in an unlawful activity with the use of the software
program, but accessoryship should be deemed to be established only in the case where
the provider has gone further to provide the software program while recommending
others to use it exclusively or mainly for the purpose of engaging in an unlawful
activity." Based on this reasoning, the court of prior instance found that when theaccused released and provided the Alleged Versions of Winny on the Internet, heperceived and accepted the possibility or probability that someone would infringe
copyright with the use of them, but the court did not find that he went further toprovide the Alleged Versions of Winny while recommending others to use themexclusively or mainly for the purpose of infringing copyright. Accordingly, the court ofprior instance concluded that the accused cannot be found guilty of accessoryship, andrendered a judgment quashing the judgment in first instance and pronouncing theaccused not guilty.
4. The defense counsels argue that accessoryship provided in Article 62, paragraph (1)of the Penal Code consists of "act of aiding," "intent of aiding," and "causality," and thejudgment in prior instance erred in construing the provisions of Article 62 of the Penal
Code in that it required "act of recommending the unlawful use" as an additional
element that constitutes accessoryship. Therefore, we examine this point, according to
the findings by the judgment in prior instance and the case records.
(1) An "accessory" set forth in Article 62, paragraph (1) of the Penal Code refers to aperson who, with the intent of contributing to another person's commission of a crime,
gives tangible or intangible aid so as to make it easy for such other person to commit acrime (see 1949 (Re) No. 1506, judgment of the Second Petty Bench of the Supreme
Court of October 1, 1949, Keishu Vol. 3, No. 10, at 1629). In other words, a person shall
9 / 29be judged to be an accessory when he/she performs an act that will make it easy for
another person to commit a crime, while perceiving and accepting such nature of
his/her act, and the principal has actually committed a criminal act. The court in priorinstance focused on the peculiar nature of the alleged act of providing thevalue-neutral software program on the Internet to many and unspecified persons, andconsidered that accessoryship is established only in the case "where the provider hasgone further to provide the software program while recommending others to use it
exclusively or mainly for the purpose of engaging in an unlawful activity." However, wecannot find that there is sufficient ground for acknowledging the establishment ofaccessoryship only in the case where the alleged person has provided the software
program to others while recommending the unlawful use, irrespective of the nature of
the software program (the likelihood of its being used for an unlawful activity) or theobjective situation of the use of the software, so we must say that the court of priorinstance erred in construing the provisions of Article 62 of the Penal Code.
(2) It is true that Winny can be used both for legitimate purposes and for the unlawful
purpose of infringing copyrights?for this reason, the judgment of first instance and thejudgment in prior instance described it as a value-neutral software?, and it is basicallyleft to each user to decide whether he/she will use Winny for the purpose of infringing
copyrights or for other purposes. In addition, the method of software development
chosen by the accused, i.e. releasing a software program under development andproviding it to many and unspecified persons on the Internet free of charge, andproceeding with the development while hearing opinions of users, is not an unusualapproach for software development but it is rather accepted as a rational approach. A
new software program to be developed will be given a wide range of evaluation insociety, and at the same time, the development process needs to be carried out swiftly.
10 / 29

Therefore, in order to avoid causing an excessive chilling effect to activities fordeveloping such software programs, providing a software program should not be
regarded as constituting an act of aiding copyright infringement only because there isa general possibility that the software program would be used for the purpose of
infringing copyright, the provider has released and provided the software program
while perceiving and accepting such possibility, and copyright infringement has
actually been committed with the use of said software. In order for such act ofproviding a software program to constitute accessoryship, there must be not only said
general possibility but further the specific circumstances where the software programis used in a manner that infringes copyright, and it is also required that the provider
perceives and accepts such circumstances. More specifically, it is appropriate toconstrue that the provider's act of releasing and providing the software program
should be regarded as constituting an act of aiding copyright infringement only in thecase (i) where a person has released and provided a software program while perceiving
and accepting a specific and immediate risk of copyright infringement to be committedwith the use of the software program, and such copyright infringement has actually
been committed and (ii) where in light of the nature of the software program, theobjective situation of use of the software program, and the method of providing it, it ishighly probable that among those who acquire the software program, a wide range of
persons will use the software program for the purpose of infringing copyright, to a level
where their use cannot be tolerated as exceptional, the provider has released andprovided the software while perceiving and accepting such high probability, and theprincipal has actually committed copyright infringement with the use of the software
program.
(3) Looking at this case from the abovementioned standpoint, first of all, it is obvious
11 / 29

that the accused did not release and provide the Alleged Versions of Winny while
perceiving or accepting a specific and immediate risk of copyright infringement to becommitted with the use of them.
Secondly, we examine whether or not it was highly probable that among those who
would acquire the Alleged Versions of Winny, a wide range of persons would use theAlleged Versions of Winny for the purpose of infringing copyright, to a level where theiruse cannot be tolerated as exceptional, and the accused released and provided theAlleged Versions of Winny while perceiving and accepting such high probability. Winnyis itself a software program which makes it possible to perform the exchange of avariety of data efficiently while maintaining secrecy of communications, and at thesame time, it is a software program which is very convenient to use when one intends
to use it in a manner that infringes copyright, as it was done by the principals of thiscase, because the commission of copyright infringement is difficult to be detected. Then,looking at the objective situation of use at the time of the incident, as pointed out in the
judgment in prior instance, there is a wide disparity with respect to the cases of
copyright infringement committed with the use of file-sharing software applications,depending on the choice of time or statistical data, so there is no evidence that
accurately shows the objective situation of the use of Winny at the time of the incident.
However, from the relevant evidence cited in the judgment in prior instance, it is atleast presumed that some 40% of the files that were flowing on the Winny network
were copyrighted works and they were exchanged among users without authorizationfrom the authors. Looking at how the accused provided the Alleged Versions of Winny,
he took measures such as posting a cautionary message to prevent users fromexchanging illegal files with the use of this software program, but he basically took theapproach of releasing the Alleged Versions of Winny on his website, free of charge and
12 / 29

on an ongoing basis, without setting any particular limit to the scope of persons who
would be able to download them. In view of these circumstances, we cannot deny thatthe accused released and provided the Alleged Versions of Winny in the situation
where it was highly probable, when viewed objectively, that a wide range of persons
would use the Alleged Versions of Winny for the purpose of infringing copyright to alevel where their use cannot be tolerated as exceptional.
On the other hand, looking at the subjective view of the accused on this point, we canfind that when the accused released and provided the Alleged Versions of Winny, heperceived that some of the users would use the Alleged Versions of Winny for the
purpose of infringing copyright or an increasing number of people had come to usethem for such purpose, but there is not sufficient evidence to go so far as to find thatthe accused perceived and accepted that the number of people who would use Winnyfor the purpose of infringing copyright had increased to a level where their use cannot
be tolerated as exceptional, and that it would be highly probable that if he released andprovided the Alleged Versions of Winny, a wide range of persons would use them for the
purpose of infringing copyright, to a level where their use cannot be tolerated as
exceptional.
In this respect, we can find the following facts: (i) On the thread where the accusedannounced the development of Winny (hereinafter referred to as the "development
thread"), a number of comments were posted by people who were expected with highprobability to attempt to use Winny for the purpose of infringing copyright, and theaccused made the announcement of the development of Winny and posted comments
regarding the development process, while perceiving that his announcement andcomments would reach such people. (ii) At the time of the incident, many stories were
circulating via the Internet and magazines, etc. to the effect that Winny kept users
13 / 29

safe from the risk of being detected and arrested for criminal charges, and the accusedhimself read these magazines. (iii) The accused himself downloaded a large amount offiles flowing on the Winny network which are presumed to be copyrighted works. Inview of these facts, it is evident that at the time of the incident, the accused perceived
that if he released and provided the Alleged Versions of Winny, some of those who
acquired the Alleged Versions of Winny would use them for the purpose of infringing
copyright, and it is also found that the accused perceived that the number of suchpeople was increasing.
However, with regard to the fact mentioned in (i), the announcement of thedevelopment and other comments that the accused posted on the development threadsomewhat indicate his desire to draw the attention of others, and what is more, thisthread was not entirely filled with comments posted by people who were expected withhigh probability to attempt to use Winny for the purpose of infringing copyright, butthere were also comments from those who were against the unlawful use of Winny, andthe accused himself posted messages on said thread to request users not to use Winnyfor the purpose of infringing copyright, such as stating "Needless to say, at present, it
is illegal to distribute works of others without their authorization. I would like to ask
beta testers not to overstep this rule when participating in the beta test. Please
remember that this is an experiment to verify whether Freenet P2P can be put into
practical application." In view of these aspects, we cannot say that the accusedreleased and provided Winny, targeting such people who were expected with highprobability to attempt to use Winny for the purpose of infringing copyright. It is also
found that at the time of the incident, the accused himself posted comments on his
website which suggested as if he expected that the spread of the use of file-sharing
software would lead to create a new business model that is different from any existing
14 / 29business models. However, as such new business model that the accused mentioned isimagined on the presupposition that the interest of authors would be properly
protected, we cannot find, only because of such comments, that the accused developed
or provided Winny for the purpose of spreading illegal copies of works on the Internet
and destroying the existing copyright system, nor can we find that he perceived or
accepted that Winny would be used mainly for infringing copyright. As for the fact
mentioned in (ii), the stories that were circulating via the Internet and magazines, etc.
cannot be deemed to accurately convey the objective situation of use at the time of theincident. It is found that at that time, based on such stories, the accused perceived thefact that an increasing number of people were using Winny for the purpose of
infringing copyright. However, considering that Winny is not designed to beuser-friendly only for the purpose of infringing copyright, we cannot go so far as to findthat the accused perceived or accepted the fact that the proportion of people who used
Winny for the purpose of infringing copyright had reached some 40%, to a level where
their use cannot be tolerated as exceptional, as indicated in the aforementioned
relevant evidence. Also with regard to the fact mentioned in (iii) that the accusedhimself downloaded a large amount of files flowing on the Winny network which arepresumed to be copyrighted works, this is only a superficial ground to show that theaccused understood the overall situation of the use of Winny at that time. Rather,
given the fact that the accused launched the development of Winny with the goal ofverifying P2P technology, and he worked on developing various versions of Winny 2,
including the Alleged Versions of Winny, with the goal of implementing a large-scalebulletin board system (BBS) using P2P technology, rather than developing afile-sharing software program, we see that the major object of his interest was atechnical aspect of the development process, i.e. to find out whether a new file-sharing
15 / 29

software program or large-scale BBS with the use of P2P technology would be actuallyoperable. In fact, Winny 2 is designed with a structure wherein the IP addresses of
those who opened threads on a BBS can be easily identified, which means that thedevelopment efforts were not made while putting emphasis only on the anonymity
function. As mentioned above, upon releasing and providing various versions of Winny2, including the Alleged Versions of Winny, the accused posted a cautionary message on
his website to request users not to exchange illegal files with the use of this software
program and also posted the same comment on the development thread, thus healways warned users not to use Winny for the purpose of infringing copyright.
In view of these circumstances, we find it difficult to go so far as to find that theaccused perceived or accepted a high probability that if he released and provided theAlleged Versions of Winny, a wide range of persons would use them for the purpose of
infringing copyright, to a level where their use cannot be tolerated as exceptional.
(4) For the reasons stated above, we should say that the accused lacked the intent ofaccessoryship to the crime of violation of the Copyright Act, so the judgment in priorinstance is justifiable in that it found the accused not guilty of accessoryship to thecrime of violation of the Copyright Act.
5. Therefore, according to Article 414 and Article 386, paragraph (1), item (iii) of theCode of Criminal Procedure, the decision has been rendered in the form of the main
text by the unanimous consent of the Justices, with the exception that there is adissenting opinion by Justice OTANI Takehiko.
The dissenting opinion by Justice OTANI Takehiko is as follows.
I disagree with the conclusion of the majority opinion and consider that the accused ofthis case is guilty of accessoryship to the crime of infringement of the right of public
transmission, which is a type of copyright. Therefore, I hereby express my dissenting
16 / 29opinion.
1. The facts of the case are indicated in detail in Section 1 of the majority opinion. The
characteristic aspect of the act of providing a file-sharing software program called
Winny, due to which the accused is charged for aiding the principals' commission of
copyright infringement, is that the software program itself is technically useful in thatit makes it possible to perform the exchange of a variety of data efficiently while
maintaining secrecy of communications, and at the same time, because of its efficiency
and its anonymity function in particular, it is also likely to infringe copyrights, which
is a legal interest, depending on how it is used (these features are two sides of the samecoin), and that the software program is provided to many and unspecified persons,with no limit to the scope of persons to whom it is provided.
A question arises as to whether or not the act of providing this kind of software
program is punishable as an act of aiding by facilitating or encouraging the principal's
act of infringing copyright (right of public transmission) by unlawfully uploading files
through infringing use of the software program. In order to punish the act of providing
as accessoryship, it is not sufficient that the act of providing entails a general or
abstract possibility of copyright infringement, but punishability as accessoryship may
be acknowledged only if the act of providing is performed in the situation where there
is a specific and higher level of probability that the principal will use the software
program in an infringing manner. On this point, my view and understanding arebasically the same as those of the majority opinion.
2. More specifically, the act of providing Winny does not itself involve any risk of
infringement of legal interest as long as it is used for a legal purpose, but if theusefulness of Winny is abused and it is used in an infringing manner, the act ofproviding it takes on the realistic risk of infringement of legal interest and becomes
17 / 29

illegal (in this sense, this act can be deemed to be a value-neutral act). Whether or not
the act of providing a software program involves any risk of infringement of legal
interest depends on the specific purpose of use or manner of use, that is, for what
purpose and for what subject users will use the software program. A mere possibility of
infringing use cannot be recognized as such risk, and only in the case where there is a
specific and higher level of probability that users will use the software program notlegally but in an infringing manner, the act of providing itself takes on the realistic
risk of infringement of legal interest and it is deemed to be illegal and punishable.
And whether or not it is probable that users will use the software program in an
infringing manner needs to be examined both from the aspect of the possibility thateach user will use the software program in an infringing manner, and in light of thefact that the software program is provided to many and unspecified persons, from the
aspect of the possibility that any one or more of those persons will use it in an
infringing manner. When estimating the former possibility, the major points to beconsidered would be whether or not the provided software program, in view of its
nature and features or the manner of providing it, can be easily used for infringing
copyright (right of public transmission) and is likely to induce infringement, andwhether or not there is any means to check the infringing use. As for the latter
possibility, if a software program which entails the possibility of infringing use is madeavailable to more people who intend to use it in an infringing manner, the higher therealistic risk of infringement of legal interest becomes (both in terms of quantity andprobability), and in this respect, matters such as the manner of providing the software
program and the scope of persons to whom it is to be provided should be taken into
consideration. Furthermore, in the objective situation where infringing use actually
has taken place quite often, the continued provision of a software program that is
18 / 29

likely to be used in an infringing manner will increase the risk of infringement of legal
interest, so the objective situation of use would be an important point to be consideredin the course of examining the aforementioned high probability.
3. Thus, in order to acknowledge punishability of the act of providing performed by theaccused, which has the characteristics as described in 1 above, it is required that thesoftware program is provided in the situation where a specific and higher level ofprobability of the infringing use can be objectively recognized. This is an illegality
element and may also be a constituent element, both of which constitute punishabilityof an act of aiding. Hence, as a subjective element required for constituting
accessoryship (intent of aiding), the alleged accessory must have perceived andaccepted such high probability (as for the identity of the principal, it is sufficient if thealleged accessory perceived and accepted said high probability at a level of what iscalled general intent).
The judgment in prior instance took one more step forward and further stated that inorder to prove that such a value-neutral act as the one disputed in this case constitutes
accessoryship, the alleged accessory must have "recommended" the infringing use.
However, as pointed out in Section 4(1) of the majority opinion, it is impossible toaccept a view that this type of accessoryship which could constitute a crime even when
the principal crime is not committed is established only in the case where the alleged
accessory has performed such a positive action.
Similarly, as a subjective element of accessoryship, it is sufficient if the alleged
accessory is found to have perceived and accepted said high probability, and it is notfurther required that he/she had the positive intention or aim of encouraging theprincipal to commit a criminal act.
4. Now, I will examine this case from the viewpoints explained above. (i) Winny,
19 / 29

developed by the accused, was not the only software program that is categorized as afile-sharing software program, but Win-MX and other software programs in thiscategory were also available, so Winny was not necessarily indispensable to infringe
copyright, the right of public transmission, on the Internet. However, through theresearch efforts of the accused, Winny has become more efficient (with the multiple
downloading function, the automatic downloading function, and the mechanism
wherein unauthorized downloading of files of copyrighted works for private use
purposes, which was not illegal at the time of the incident, would immediately lead to
uploading those files, which now constitutes an illegal form of public transmission),and the anonymity function has also been attached to it (e.g. a mechanism wherein
after a file is relayed, it becomes difficult to track the position information (keyinformation) of the point from which the file was sent). As a result, Winny is so easy to
use in an infringing manner despite the warning message posted for checking such use
and also so tempting toward using it in an infringing manner, that users would be
encouraged to engage in infringing use. (ii) Looking at the manner of providing Winny,
it is provided to many and unspecified persons widely and with no limit, and anyone
can access Winny at any time without submitting an application or obtaining consent
for use, without any restriction on use. (iii) The objective situation of use is asmentioned in Section 4(3) of the majority opinion: there is no evidence that accurately
shows the situation of the use of Winny at the time of the incident (2003), but from therelevant evidence cited in the judgment in prior instance, it is at least presumed thatsome 40% of the files that were flowing on the Winny network were copyrighted works
and they were exchanged among users without authorization from the authors.
Given all of these circumstances, at least with regard to the act of releasing andproviding the Alleged Versions of Winny that was performed in September 2003, it is
20 / 29

sufficiently possible to recognize the "high probability" of infringing use objectively, inlight of the easiness of the infringing use of the software program provided, the natureand features of the software program that are likely to encourage such use, and themanner of providing the software program with no limit to the scope of persons towhom it was provided, as well as the abovementioned objective situation of use.
I would additionally mention that said proportion of the files which are presumed tohave been involved in the infringing use, some 40%, is estimated partly based on thesurvey on copyright infringement, targeting the 1.2 million sample of file information(keys) that were circulating on Winny at a certain point in time, which showed thatsome 40% of these files were pure copies of commercially available copyrighted works
such as music files and DVDs. This means that, even on the sampling basis, as manyas some 400,000 pure copies of commercially available copyrighted works were
circulating. This cannot be regarded as an exceptional situation of the infringing use of
Winny. In addition, according to another survey conducted by a certain association
with regard to about 20,000 items of file information (keys), which was examined by
the court of prior instance, about 50% of them were copyrighted works of video, music,
and game software, and about 90% of these works are presumed to have been usedwithout authorization (judgment in prior instance, page 20). Although an accurate
number of Winny users cannot be ascertained, there is also a survey that indicates thatabout 3% of all Internet users (presumed to be slightly more than 30 million at thetime of the incident) used file-sharing software programs (judgment in first instance,
page 15), and about one-third of them used Winny most frequently. If the rate of use issubstituted for the volume (number) of users, one can presume that Winny was used in
an infringing manner by a great number of people to a level where their use cannot at
all be considered to be exceptional, even while taking into consideration the defective
21 / 29aspects of these surveys as argued by the defense counsels. As these surveys include asurvey conducted in 2006, two and a half years after the incident, in consideration of
the increase in the number of users of file-sharing software programs during thisperiod, one must necessarily revise the estimate downward to a certain degree in orderto presume the situation at the time of the incident based on these data. Nevertheless,the presumption explained above basically seems valid.
5. As mentioned in 3 above, as a subjective element required for accessoryship, theaccessory must have the intent of aiding, in the form of perceiving and accepting suchhigh probability as objectively recognized. The majority opinion, in its conclusion, does
not find the intent of aiding on the part of the accused, explaining that it is difficult togo so far as to find that the accused perceived or accepted a high probability that awide range of persons would use the software program in question for the purpose of
infringing copyrights, to a level where their use cannot be tolerated as exceptional. In
my view, the accused of this case can be found to have perceived and accepted the highprobability of the infringing use, and this is the essential reason why I dissent from the
majority opinion.
(1) As for the probability of infringing use, the accused, as the developer of the software
program, must have perceived that the software program was easily used in an
infringing manner and was likely to encourage such infringing use because of its
usefulness, and that the software program was provided to a wide and unlimited scopeof persons. With regard to the objective situation of use, the accused may not haveperceived the actual situation of use on a statistical basis, that is, about 40% of the useof the software program was conducted in an infringing manner, because no accurate
survey of use was available at the time of the incident. However, in light of the factors
pointed out in Section 4(3) of the majority opinion, namely, (i) the comments posted by
22 / 29

users on the thread where the accused announced the development of the software
program, which imply their attempt of infringing use, (ii) his access to magazine
articles and other information concerning the infringing use of Winny, which wereavailable at the time of the incident, and (iii) the records of his downloading of files of
copyrighted works, I should say that the accused perceived that Winny was being usedin an infringing manner and its use was spreading to a considerably wide range ofusers (to a level where their use cannot be tolerated as exceptional).
The circumstances pertaining to the perception and acceptance of the accused in
respect of the situation of the infringing use, as pointed out by the majority opinion,
may be worthy of careful consideration as the factors leading to denying that theaccused perceived the probability of the infringing use. However, even taking into
consideration these circumstances as well as the characteristics of the personality of
the accused, i.e. his orientation as a researcher and developer, that is, his inclinationand devotion to achieving usefulness, the positive side of research and development,
and on the other hand, his lack of attention and carelessness to the negative side, theinfringing use which could occur as a side effect, I would say that all of these are notenough to deny that the accused perceived the high probability of infringing use. If theaccused continued to provide the software program while perceiving such objective
situation concerning the high probability of the infringing use, he should basically befound to have also accepted the high probability of the infringing use.
(2) As mentioned above, in the process of determining whether or not there is theintent of aiding in the case where such act of providing technology as the one disputedin this case is both technically useful and likely to cause infringement of legal interest,
and where the technology is provided to many and unspecified persons, if it isconstrued that the intent of aiding is found only where the alleged accessory has a
23 / 29

positive intention or aim of infringing legal interest in addition to an intent of aiding in
general, such construction has no sufficient ground and I cannot help but hesitate toagree with it.
In agreement with the majority opinion, I do not find such a positive intent of
infringement in the accused as alleged by the public prosecutor, for instance, wishingfor the spread of illegal copies of works with the use of Winny or developing andproviding Winny mainly for the purpose of making it available for infringing use. I am
willing to acknowledge that the accused engaged in developing and providing thesoftware program mainly for the purpose of making it possible to perform the exchange
of a variety of data efficiently while maintaining secrecy of communications.
As the factors for judging that the accused lacked the intent of aiding, the majority
opinion point out the circumstances such as that the accused posted comments on thedevelopment thread to express his intention of developing and providing the software
program, he expected a new business model to be created with the use of the software
program on the presupposition that the interest of authors would be properly protected,
and he posted a message to warn users not to use the software program in an
infringing manner. All of these circumstances may be understandable as the grounds
for finding that the accused lacked a positive intention of infringing legal interest, butthey are not necessarily inconsistent with or contradictory to the view that heperceived and accepted the risk of infringement of legal interest. Rather, one would
infer that because he perceived the risk that his act of providing the software program
would lead to infringement of legal interest, he posted a warning message to express
that such infringing use was not what he intended or aimed and was contrary to histrue intention. While issuing such message, the accused still engaged in the act ofproviding without taking any measures to check the infringing use, so in this respect,
24 / 29

he should inevitably be found to have perceived and accepted the high probability of
the infringing use.
6. For the reasons stated above, I consider it possible to find that the act of the accusedmeets the constituent requirements for accessoryship and he had the intent of aiding.
Meanwhile, since the defense counsels seemingly also argue that his act should besubstantially exempt from legal liability, I would like to give some comments on thispoint as well.
As explained above, it is found that the accused developed and provided Winny mainly
for the purpose of pursuing technical usefulness, that is, improving the efficiency andanonymity of P2P-based file-sharing software programs and making it possible toperform exchanges of a variety of data efficiently while maintaining secrecy ofcommunications. The method of software development chosen by the accused, i.e.
proceeding with development while providing a software program to many andunspecified persons and hearing users' opinions, does not seem to be particularly
unreasonable.
In view of these points, there may be some room in this case to discuss whether or not
the act of the accused should be substantially exempt from legal liability, if his act isdeemed to be allowable according to the generally accepted social standards while
comprehensively taking into account the relevant factors such as the purpose of the act,
the appropriateness of the means chosen, comparison as to infringement of legal
interest, and policy-based consideration, or allowable from the viewpoint of the law
system as a whole.
It is true that in this case, it is the persons prosecuted as the principals who actuallycommitted copyright infringement, and the accused, by providing Winny, only provided
the principals with one means for their commission of the crime. Furthermore, Winny
25 / 29

was not the only file-sharing software program that was available as such means, and
Win-MX was used more frequently as P2P-based software. Thus, the act of the accusedto provide Winny had a weak effect in causing copyright infringement or infringementof legal interest, so there may be a view that the accused cannot be held liable in tort
under civil law. In this sense, it may be possible to find him guilty only of a minor
crime.
However, although the software program may not play a significant role in committing
each act of infringement, in light of the nature and the method of provision of theAlleged Versions of Winny, i.e. they can be easily used in an infringing manner andthey are provided to many and specified persons with no limit, the Alleged Versions ofWinny are likely to provoke a large number of copyright infringement cases, and inreality, such infringing use frequently took place as explained above. Thus, in terms ofinfringement of legal interest, it may be possible to consider that the Alleged Versionsof Winny entail such level of risk that cannot be overlooked in society. In this context,
the legal interest that might be infringed should be protected by imposing
imprisonment with work (at the time of the incident, imprisonment with work for not
more than three years) against infringement.
On the other hand, the act of developing and providing the software program
performed by the accused has been evaluated as being useful to a certain extent in theInternet society. However, in this technical field, progress in technological development
takes place rapidly, so it is considerably difficult to obtain an objective evaluation
based on adequate verification in the relevant field.
Such features of the Alleged Versions of Winny, i.e. usefulness and likelihood of
infringement of legal interest, may not be suitable for relative comparison of legal
interest. As usefulness of the Alleged Versions of Winny is already taken into
26 / 29

consideration in the phase of discussing the high probability of infringing use as theelement to constitute accessoryship, it seems to be inappropriate to take this point into
consideration again in the course of discussing the issue of substantial exemption fromliability.
(In connection with the aforementioned aspect of policy-based consideration, it is found,
as explained above, that Winny, the software program developed and provided by theaccused, is technically useful for the distribution of information on the Internet, andthe accused engaged in developing and providing it mainly for the purpose of pursuingsuch usefulness. When it comes to promotion and advancement of technical usefulness
in the field of information distribution, dealing with the risk of infringement of otherkinds of legal interest, which could occur as a side effect, by immediately imposing
criminal penalty, could result in excessive restriction on the development of innovativetechnologies and impedance to technological advancement, and could ultimately causea chilling effect on technological development in other fields. Viewing the situation andgiving consideration from this perspective, a careful and restrained attitude isrequired for criminalizing the act of providing technology that has only served as ameans for the principal to commit infringement of legal interest and punishing it asaccessoryship. This consideration may lay behind the conclusion drawn by the majority
opinion that decided not to punish the accused. In this case, before the accusedreceived any complaint from authors or other right holders or any official alarm wasgiven to file-sharing software program providers in general in society, the law
execution authorities set about investigation and carried out compulsory investigationin response to the accusation, and then prosecuted the accused on the presupposition
that he provided the software program for the purpose of spreading copyright
infringement. Seeing such developments of the case, I would say that the authorities
27 / 29

somewhat lacked consideration to this point and acted too hastily. In addition, there
are also circumstances in favor of the accused, such as that he did not have any intent
of making profit, and he quickly closed the website where Winny was made available tothe public, after he was advised by the law execution authorities.
At the same time, if the activities of developing and providing technology in a certain
field put too much emphasis on pursuing a benefit, this could, as a side effect of such
benefit, cause infringement of other kinds of legal interest. Hence, as long as thedeveloper of technology intends to provide the technology widely in society with nolimit to users, he/she should proceed with development while giving due consideration
to this aspect, as his/her responsibility in society as a developer. In my view, for thereasons stated in 1 to 5 above, the accused is found guilty of accessoryship, and theaforementioned circumstances in favor of him should be sufficiently taken into accountin determining his sentence for accessoryship, including commutation.)
7. For the reasons stated above, I consider that the judgment in prior instance should
inevitably be quashed.
=================================================================
Presiding Judge–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Justice OKABE Kiyoko
Justice NASU Kohei
Justice TAHARA Mutsuo
Justice OTANI Takehiko
Justice TERADA Itsuro=================================================================
note_other28 / 29

–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––(This translation is provisional and subject to revision.)

29 / 29