Anonymous X post sparks debate over AI use in Heated Rivalry fanfic

In short: An anonymous X account shared a 25-page report accusing 38 popular Heated Rivalry fanfics of using text from Anthropic’s Claude chatbot, and the fandom erupted into a multi-platform fight.

What happened

A new anonymous X account, @atedrryai, posted a link to a 25-page document about fanfiction based on Heated Rivalry, a male-male hockey romance story with an enemies-to-lovers plot. The document listed 38 well-known stories and said they contained text generated by Claude, a chatbot that can write passages on request.

The author framed the post like an investigation and named specific works, including stories by some of the fandom’s most popular writers. After posting, the account urged people to “treat each other with kindness,” but arguments kept escalating. Some fans nicknamed the document the “fan fiction Panama Papers,” meaning it felt like a leak that exposed people and invited scrutiny.

Why it mattered

The document’s main evidence was not just “this sounds like AI.” It described a leftover code marker that can appear when someone copies Claude’s text into Archive of Our Own, often called AO3, a major fanfiction site. The marker was the HTML tag font-clude-response-body (HTML is the behind-the-scenes formatting code, like a hidden label on a package).

By searching for that tag inside AO3 pages, the author said they could spot where Claude text had been pasted. The document also shared code that could highlight those sections in bright red, and claimed some stories had hundreds of matches.

The fallout spread across X, Threads, Reddit, Bluesky, and TikTok. People argued about trust, whether AI help should be disclosed, and whether naming authors was accountability or public shaming.

Source: NYTimes