On April 25 2018, the Japan Intellectual Property High Court gave a decision that made Twitter users uneasy.

In this case, a photographer who has the copyright of a photo demanded Twitter, Inc. and Twitter Japan disclose the information on the user who had posted the photo on Twitter without permission from the photographer as well as the information on the users who had retweeted that Tweet using the Twitter Retweet function.

For the user who tweeted the photo, the court ruled that Tweet represents copyright infringement and ordered Twitter, Inc. to disclose the user information (i.e. email address) to the photographer. On the other hand, for the users who retweeted the copyright infringing Tweet, the court denied copyright infringement. The above is the same result as the lower-court ruling. However, the IP High Court judges ruled that Retweet represents moral rights infringement and made an order for disclosure of the user information.

The photo in the case shows a sign of “reproduction prohibited” in the upper part, and the copyright mark followed by the name of the photographer and his autograph in the lower part. On the other hand, the photo reproduced by the Retweet function is trimmed and resized so as to shorten the vertical size. As a result, the sign of “reproduction prohibited”, the copyright mark, and the name and autograph of the photographer are trimmed off. The process of the Twitter Retweet function caused moral rights infringement.

Please note that the retweeted Tweet is a copyright infringing one in this case. In a normal case, a person who posts contents on Twitter permits Twitter, Inc. to process, adapt, and modify the contents in accordance with Twitter Terms of Service.

“By submitting, posting or displaying Content on or through the Services, you grant us a worldwide, non-exclusive, royalty-free license (with the right to sublicense) to use, copy, reproduce, process, adapt, modify, publish, transmit, display and distribute such Content in any and all media or distribution methods (now known or later developed).”

Meanwhile, the user who tweeted the photo in this case also violated the Twitter Terms of Service which requires users to have or have obtained permissions necessary to tweet contents.

“You represent and warrant that you have, or have obtained, all rights, licenses, consents, permissions, power and/or authority necessary to grant the rights granted herein for any Content that you submit, post or display on or through the Services. You agree that such Content will not contain material subject to copyright or other proprietary rights, unless you have necessary permission or are otherwise legally entitled to post the material and to grant Twitter the license described above.”

Even if such a problem occurs only when users retweet copyright infringing Tweets, some users possibly hesitate to retweet others’ Tweets. Because it is hard for users to judge whether or not the Tweet infringes other person’s copyright every time they want to retweet. Also, it is not unusual for users to behave in the anticipation that other users obey the terms and conditions.

In order to prevent innocent users from getting involved in such copyright disputes, I expect Twitter to review the process of the Retweet function on the contents.

By the way, the court rejected the photographer’s claim against Twitter Japan, considering the luck of authority to disclose such user information.