In a recent, groundbreaking decision, the IP High Court addressed the issue of inline linking in retweets with regard to a claim brought under the Act on the Limitation of Liability for Damages of Specified Telecommunications Service Providers and the Right to Demand Disclosure of Identification Information of the Senders (the Act on Providers' Liability).(1)

'Inline linking' is the use of an image or object from one website on another website.(2) In this case, a photograph taken by the plaintiff was used in one tweet in a way that infringed his copyright and moral right. The original tweet was then retweeted by Twitter users, effectively inline linking the original tweet which displayed the plaintiff's photograph. The plaintiff petitioned the IP High Court for the disclosure of:

  • the email and IP address of each Twitter user who had retweeted the original infringing tweet; and
  • the time stamp for when they most recently logged in.

Based on the Act on Provider's Liability, the IP High Court granted the plaintiff's claim for disclosure of the users' email addresses. In its ruling, the court held that the plaintiff's photograph had been modified in each retweet by using a HTML or CSS program, thereby infringing the plaintiff's moral rights (in particular, his right to integrity and his right to attribution).

However, the IP High Court dismissed the petition for the disclosure of the IP addresses and log-in time stamps, as these were deemed to be irrelevant and unnecessary for the plaintiff to be able to exercise his right to claim damages.

This decision sets a precedent in Japan regarding liability for inline linking. It demonstrates that Twitter users may be liable for the infringement of a party's copyright or moral right when inline-linked images are contained in retweets.

For further information on this topic please contact Kei Akagawa at Anderson Mori & Tomotsune by telephone (+81 3 6775 1000) or email ( The Anderson Mori & Tomotsune website can be accessed at


(1) Act 137/2001, available here.

(2) Perfect 10 v Google, Inc, 416 F Supp.2d 828 (2006).

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