Civil Liability for BitTorrent Infringement in Japan: A Framework Overview

This note is a general overview of Japanese law, written for an exchange of views among practitioners. It is not legal advice, does not concern any specific case, and is not an offer of legal services in any jurisdiction.

Why we are writing this

Japanese audiovisual and other content is shared through BitTorrent networks well beyond Japan. Rights holders and counsel in different countries face the same structural questions: how to identify participants, how to frame liability, and how to measure damages in a system where every participant both downloads and uploads. We would like to compare approaches with colleagues who work on these problems elsewhere. This note sets out the Japanese side as a starting point.

The civil procedure in three stages

In Japan, civil claims against BitTorrent participants generally proceed in the following order. The durations below are rough indications only and vary by case.

• Disclosure of subscriber information. Because participants are anonymous, the rights holder first seeks disclosure from the internet service provider under the Provider Liability Limitation Act. This identifies the name and address of the line subscriber (roughly six months to one year).
• Notice and negotiation. Counsel for the rights holder sends a notice to the subscriber, and the parties may resolve the matter by agreement (roughly one to six months).
• Civil litigation. If negotiation fails, a damages suit may be filed (roughly one to two years at first instance).

The leading decision

The leading decision on the civil liability of BitTorrent users in Japan is the judgment of the Intellectual Property High Court of April 20, 2022 (Reiwa 4), Case No. Reiwa 3 (Ne) 10074. On damages, the court held that each download of a file deprives the copyright holder of an opportunity to sell one download or stream of the work, and calculated damages on the basis of the sales price. Because the participants in a BitTorrent network realize file sharing by exchanging pieces with one another, the court also recognized joint tort liability under Article 719(1) of the Civil Code.

For the standard of damages, please refer to the judgment itself.

Questions we would like to compare

We would welcome the views of colleagues on the following, from any jurisdiction:

• How is liability of swarm participants framed in your system: joint liability, contributory infringement, or another theory? Does it extend to the whole swarm or only to a participant’s own transmissions?
• How is damages measured where a work is distributed by many participants? Is a per-download or lost-sale approach used?
• What mechanism exists to obtain subscriber information from providers (for example, court-ordered disclosure or subpoena procedures), and how long does it take?
• Can the costs of the disclosure stage be recovered from the defendant?

Get in touch

If you work on these questions and would like to exchange views, please write to us. We will discuss the law and practice in general terms only.