An Amsterdam district court ruled this week that fansubbing, the practice of fan-made subtitles for TV shows and movies, is illegal.

The case was brought by a Dutch group called the Free Subtitles Foundation, which sued Netherlands' anti-piracy BREIN to clarify if the creators of a TV show or movie can reserve the right to produce subtitles or if fans can create their own on fair use grounds.

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The court found subtitles can only be created and distributed with permission from the rights holders. Any unauthorized subtitles, including those created by fans, are considered to be copyright infringement.

"With this decision in hand it will be easier for BREIN to maintain its work against illegal subtitlers and against sites and services that collect illegal subtitles and add movies and TV shows from an illegal source," BREIN director Tim Kuik said in a statement.

BREIN was not entirely unsympathetic to the case that fansubbing makes content more accessible to audiences who would otherwise not be able to enjoy the media, but the group held most fan-made subtitles were used by people who pirated the content and may encourage further piracy.

The fansubbing community is massive, with hundreds of sites offering fan-made closed captioning files that are downloaded millions of times. It’s difficult if not impossible for those producing or hosting the subtitles to know if the person using them obtained the related content illegally. In many cases, fansubbing fills in the gaps for TV shows and movies that only offer captions in limited languages.

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The issue is exacerbated by the fact many copyright holders release content at different times in different regions, allowing fansubbing to provide a way to watch and understand content that is otherwise not yet available.

The court ruling may set a precedent that will present challenges for the fansubbing communities, but it is unlikely the practice will stop. In some cases, like in anime communities, fansubbers start offering translations for streaming websites rather than downloads.

While BREIN and copyright holders may be trying to push fansubbing away, others have begun to embrace it. Netflix offers payment for those who can help with translations for subtitles, and YouTube also encourages crowdsourced captions for videos.