Japanese authorities have arrested a man accused of acting as the “First Uploader” (Seeder) behind pirated content distributed through Nyaa (nyaa.si), one of the world’s largest torrent indexes for anime, manga, games, and other Japanese media.
The arrest, announced by Japanese anti-piracy organization CODA, is being described as a landmark case in the fight against online copyright infringement, with investigators targeting not the operators of a piracy website, but the individual allegedly responsible for introducing copyrighted content into the BitTorrent network.
According to Kyoto Prefectural Police, the suspect, a resident of Sagamihara City in Kanagawa Prefecture, was arrested on July 28, 2026, on suspicion of violating Japan’s Copyright Act after allegedly uploading the NHK drama Midnight Taxi without authorization.
Authorities believe the suspect did far more than upload a single television series, alleging that he also shared numerous NHK dramas through the platform over an extended period.
What Is Nyaa?
For anime fans, Nyaa has long been one of the internet’s most recognizable torrent indexes for Japanese media.
Unlike traditional piracy websites that directly host copyrighted videos or files, Nyaa functions as an index of torrent files. These files do not contain the copyrighted content itself. Instead, they provide information that allows users to connect to others through the BitTorrent peer-to-peer (P2P) network, where the files are shared directly between users’ computers.
Because the content is distributed across thousands of individual users rather than stored on a central server, torrent-based piracy has historically been much more difficult for copyright holders to combat.
According to CODA, Nyaa remains one of the largest torrent platforms in the world, averaging around 30 million monthly visits between July 2025 and June 2026. Roughly half of those visits are believed to come from users in Japan, where newly aired anime, television dramas, films, and other Japanese content are frequently uploaded shortly after broadcast.
Why Authorities Targeted the “First Uploader”
Rather than pursuing ordinary downloaders, investigators focused on what is known as a First Uploader, or Seeder.
In the BitTorrent ecosystem, the First Uploader is the individual who introduces a complete copy of a file into the network. Once other users begin downloading pieces of that file, they also begin uploading those pieces to others, allowing the content to spread rapidly across thousands of computers.
In other words, every torrent begins with a single source.
Because of this, CODA considers the First Uploader to be the starting point of copyright infringement on peer-to-peer networks.
The organization says that identifying and prosecuting those responsible for creating the initial torrent can have a much greater impact than targeting users who later download or redistribute the same content.
According to investigators, the suspect allegedly published the torrent file for Midnight Taxi, enabling an unspecified number of users to begin sharing the drama across the BitTorrent network. Authorities also suspect he uploaded numerous additional NHK programs through Nyaa.
Why Nyaa Has Become a Major Focus
CODA says Nyaa has become one of the primary sources from which pirated Japanese content spreads across the internet.
The organization pointed to a previous criminal investigation involving B9GOOD, one of Japan’s largest anime piracy websites before it was shut down in 2023.
According to CODA, operators behind B9GOOD admitted during the investigation that they obtained much of their content from Nyaa before redistributing it through their streaming platform.
Because of cases like these, Japanese authorities believe Nyaa plays a significant role in the broader piracy ecosystem, acting as one of the earliest distribution points for newly released anime, dramas, and other entertainment.
Rather than existing in isolation, torrent uploads published on Nyaa can eventually spread across streaming sites, file-hosting services, and countless other piracy platforms.
Investigation Began More Than Five Years Ago
The arrest is the result of a lengthy investigation rather than a sudden enforcement action.
CODA revealed that the case originated in 2021 through its Cross Border Enforcement Project (CBEP), an anti-piracy initiative supported by Japan’s Ministry of Economy, Trade and Industry.
As part of the project, investigators began analyzing activity on Nyaa in an effort to identify the individuals responsible for uploading copyrighted works.
According to CODA, investigators successfully obtained information about the suspect using an analysis tool developed by the Japan Hacker Association, which participated in the CBEP initiative.
After gathering the necessary evidence, Kyoto Prefectural Police carried out their own investigation before identifying and arresting the suspect. CODA then coordinated with affected Japanese copyright holders, ultimately leading to the criminal case announced this week.
CODA Has Been Targeting Nyaa for Years
The latest arrest is only one part of a much broader campaign against torrent-based piracy.
CODA revealed that it has spent years implementing measures aimed at limiting Nyaa’s reach.
One notable effort came in 2019, when the organization worked with Google to remove Nyaa’s homepage from Google Search results, making it more difficult for users to discover the website through standard searches.
While that move did not shut the platform down, it reflected a growing strategy of disrupting piracy through multiple approaches rather than relying solely on website takedowns.
The organization has since expanded those efforts through investigations, legal cooperation, and international enforcement projects.
Authorities Previously Arrested Secondary Uploaders
The newly announced case also follows several related arrests made in 2025.
Before identifying the alleged First Uploader, Kyoto Prefectural Police arrested three secondary uploaders who allegedly redistributed copyrighted content through websites linking to torrent files originally published on Nyaa.
Those cases involved copyrighted works owned by CODA member companies, including:
- Re:ZERO -Starting Life in Another World- Season 3
- Kowloon Generic Romance
- Mobile Suit Gundam GQuuuuuuX
Unlike a First Uploader, a secondary uploader republishes or redistributes content that has already entered the BitTorrent network.
CODA says pursuing both types of offenders sends a clear message that criminal liability may extend beyond the original source of pirated content.
Torrent Users Also Received a Warning
Alongside announcing the arrest, CODA issued a warning aimed at ordinary BitTorrent users.
The organization noted that many torrent applications automatically upload portions of downloaded files to other users while the download is still in progress.
As a result, users may unknowingly participate in distributing copyrighted material even if they believe they are only downloading it.
CODA further warned that knowingly downloading pirated content may also violate Japan’s Copyright Act depending on the circumstances.
“In order to show respect for works created through the ingenuity and tireless efforts of creators and to support the healthy development of culture, we ask that you enjoy content through legitimate channels and refrain from using pirated content,” the organization said.
A New Strategy Against Anime Piracy
Rather than focusing exclusively on shutting down piracy websites, Japanese authorities increasingly appear to be targeting the individuals responsible for introducing copyrighted content into peer-to-peer networks.
By arresting an alleged First Uploader on one of the world’s largest torrent indexes, investigators hope to disrupt piracy at its earliest stage—before copyrighted works spread across thousands of users and eventually appear on streaming piracy websites around the world.
Whether this strategy leads to additional arrests remains to be seen, but CODA has described the case as a significant milestone in its campaign against torrent-based copyright infringement and says it will continue monitoring similar activities as the investigation and any future criminal proceedings move forward.
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Source: CODA
