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Press Release


Yahoo! JAPAN Publishes Media Transparency Report Summarizing Response to Guideline-Violating Posts

- Provides with transparency, a full explanation of
the status of actions in FY2020
- Aims to enhance and reinforce measures against guideline-violating posts (e.g., defamatory comments)

Media Transparency Report (Japanese only)

Yahoo Japan Corporation (hereinafter “Yahoo! JAPAN”) has today published the Media Transparency Report for fiscal 2020 (hereinafter the “Report”) *1 which summarizes its actions against guideline-violating posts*2 (e.g., defamatory comments).

Yahoo! JAPAN will make voluntary countermeasures toward defamatory posts with transparency, and will incorporate external views to further enhance and reinforce its countermeasures.

The Report is formulated based on the recommendations (hereinafter the “Recommendations”) received from the Panel on the Operation of Platform Services*3 (hereinafter the “Panel”) on December 22, 2020.

The Panel, consisting of outside experts in various fields, including law and the media, compiled the Recommendations based on their wide range of opinions, on how to deal with postings that are libelous or slanderous. As one of the main items in the Recommendations, the Panel expects the platform operators to make their initiatives more transparent.

Yahoo! JAPAN also firmly acknowledges the importance of providing thorough explanations to the public on its individual measures to deter and reduce guideline-violating posts, the algorithm for AI-based removals, as well as the system design to ensure rationality.

This Report covers the comment section of Yahoo! JAPAN News and Yahoo! JAPAN Knowledge Search, which are the major user-generated platform services. The Report provides explanation on the monitoring system for posts, reasons for deletion, and the status of actions based on the Provider Liability Limitation Act, along with figures and breakdowns. This is the first time Yahoo! JAPAN publishes a Media Transparency Report on how it deals with defamatory posts that violate its guidelines. Yahoo! JAPAN will continue to release, on a regular basis, the latest information on the status of measures taken.

In the future, Yahoo! JAPAN will build an ecosystem for continuous improvement of its voluntary efforts against defamation, etc., for example, by collecting and incorporating feedback from users and external experts on the content of this Report, reviewing the items that should be made public, and re-evaluating its initiatives.

Yahoo! JAPAN believes that providing a forum that many users can readily use, while at the same time ensuring safety and security, is of utmost importance. Since the start of the user-generated platform services, Yahoo! JAPAN has worked to eliminate guideline-violating posts chiefly through its measures against defamatory posts. In addition to round-the-clock human patrols by a dedicated team, Yahoo! JAPAN uses technologies such as its internally developed natural language processing model (AI) using deep learning*4 for these measures. As a result, Yahoo! JAPAN News currently removes approximately 350,000 posts out of an average of 10.5 million posts made in a month, and Yahoo! JAPAN Knowledge Search approximately 300,000 posts out of an average of 4.5 million posts made in a month*5.

Yahoo! JAPAN will continue fulfilling its social responsibilities as an Internet service company, by reinforcing its measures against defamatory postings in its services, while balancing it with the freedom of expression of the users. Furthermore, while ensuring a high level of transparency, Yahoo! JAPAN will continue to make improvements so that many users can use its services with a sense of security.

■Comment from Panel Chairperson, Tatsuhiko Yamamoto (Professor, Keio University Law School)
Recognizing that defamatory posts made by users pose a serious social problem, the Panel recommended proactive measures to be taken to deter defamatory postings on the comment section of Yahoo! JAPAN News, etc., including the use of AI. At the same time, we called for thorough transparency and accountability to prevent the excessive deletion of appropriate posts and excessive silencing of expressive activities.

The release of a Media Transparency Report, that discloses the monitoring system for posts, the number of posts removed, and the reasons for removal, in response to the Recommendations, is highly commendable and fulfills the social responsibility of a platform provider, which now has a tremendous influence on the forum for speech.

That said, this report is only a first step toward the formation of a free and democratic digital society based on platform services. It is imperative that the opinions and criticisms from users and the media be sincerely received, the post monitoring system be constantly reviewed, and the areas requiring transparency be regularly scrutinized. I also hope that Yahoo! JAPAN will make efforts to ensure the transparency of its new function that automatically hides the comment section, which was introduced in October.

■ Outline of the Media Transparency Report (Japanese only)
- Reason for compiling the Media Transparency Report
- System for monitoring posts
- Patrol system
- Automatic response
- Usage status of Yahoo! JAPAN News and Yahoo! JAPAN Knowledge Search
- Breakdown of reasons for removals
- Status of responses made based on the Provider Liability Limitation Act
- Response to sanctioned users

*1 The Report is a summary of the countermeasures taken in fiscal 2020. New measures implemented from fiscal 2021 are scheduled to be published in 2022 in the FY2021 Transparency Report.
The verification results of the function that automatically hides the comment section implemented from October 19, 2021*6 are scheduled to be announced separately.

*2 Guideline-violating posts refer to posts that violate the following policies and rules:
- Terms of Use
- Yahoo! JAPAN News Comment Policy (Japanese only)
- Rules on Using Yahoo! JAPAN Knowledge Search (Japanese only)

*3 Yahoo! JAPAN Formulates Response Policy to Slanderous Comments against Individuals and Future Policy (December 23, 2020) (Japanese only)

*4 Countermeasures Taken by Yahoo! JAPAN News against Inappropriate Comments Utilizing Its Large-Scale Deep Learning Model (Yahoo! JAPAN Tech Blog, April 19, 2021) (Japanese only)

*5 As of March 2021

*6 Yahoo! JAPAN News Strengthens Measures to Improve the Integrity of the Comment Section (October 19, 2021)

[Outline of Panel on the Operation of Platform Services]
1. Agenda
- Directions of services
- Effectiveness and validity of AI-based measures
- Securement of removal standards and transparency of actual actions taken

2. Panel members (names listed without honorifics)
Tatsuhiko Yamamoto - Professor, Keio University Law School

Hajime Ogawa - Advisor, The Mainichi Newspapers Group Holdings Co. Ltd.
Toshiko Sawada - Director, EC Network
Kazuhiro Maeshima - Professor and Dean, Faculty of Global Studies, Sophia University
Ryoji Mori - Attorney-at-Law, Eichi Law Offices
Noriyuki Yanagawa - Professor, Faculty of Economics, Graduate School of Economics, The University of Tokyo
Shinichi Yamaguchi - Associate Professor, Center for Global Communications, International University of Japan

Response to Posts that Contain Slanderous or Defamatory Content against Individuals (June 1, 2020) (Japanese only)

Yahoo! JAPAN Establishes Panel on the Operation of Platform Services to Formulate Voluntary Rules (July 1, 2020) (Japanese only)

Initiatives Undertaken to Make the Yahoo! JAPAN Comment Section a Healthy Forum of Discussions (June 24, 2020, Yahoo! JAPAN Corporate Blog, Japanese only)

Initiatives Undertaken by Yahoo! JAPAN News Comment (Summary) – Making the Comment Section a Safe and Secure Forum for Discussions – (Updated as needed, Japanese only)

Unless otherwise specified, English-language documents are prepared solely for the convenience of non-Japanese speakers. If there is any inconsistency between the English-language documents and the Japanese-language documents, the Japanese-language documents will prevail.