Six months after Google’s Gemini AI model suggested people use glue as an ingredient in pizza, the feature is still struggling to separate fact from fiction.

Search for “who invented the backflip,” and up until a few weeks ago, Gemini would tell you all about John Backflip, who apparently first mastered the move in Medieval Europe in 1316. And if you search “who is John Backflip,” Google’s AI credits him with inventing the gymnastic skill. But the source for this information is a TikTok video from American gymnast Ian Gunther, who made up the story entirely.

“I like making satirical videos on gymnastics and you can get away with goofing and making some jokes about the sport,” he told Forbes.

Google’s Gemini AI produces an “overview” that’s been embedded at the top of search results for six months, and it’s gotten off to a rocky start. The AI Overview’s claim that eating rocks had nutritional benefits and Barack Obama was the United States’ first Muslim President not only made the company the butt of online jokes but became a watchword for the limitations of large language models.

Gunther, who was formerly on Team USA and won the NCAA championship in 2023, cooked up the back story for John Backflip after a training session at his Bay Area gym back in May 2023. “Most skills in gymnastics are named after the first person to compete it internationally,” said Gunther. “I went home and made a goofy backstory for someone inventing the backflip.”

If anyone missed the joke, Gunter also goes on to cite ‘Henry MuscleUp’, ‘Richard Presshandstand’ and ‘Alfonso El Grip’ as other early gymnastics pioneers. The video was a modest hit on Gunther’s YouTube and TikTok, where he posts clips from training sessions and competitions, but he had mostly forgotten about the clip until he got a text in July. “It was a screenshot of the AI and I was like, ‘oh no, what have I done?’ Am I the spreader of disinformation?”

Screenshots of the AI summary about John Backflip were shared on Reddit and other social networks and even earned a corrective tweet from dictionary publisher Merriam-Webster.

Google’s AI Overview searches about the inventor of the backflip now note that this is an internet meme but still parrot Gunther’s video verbatim in searches about John Backflip. When Forbes tested rival AI platforms like OpenAI, Anthropic and Perplexity, they either also clocked the joke, or noted that there is no accurate source on the first person to perform a backflip.

Gunther is still puzzled at why Google picked up the video. “They probably shouldn’t use my videos as any sort of source,” he said.

The video appears to have exploited several weak spots in the design of Google AI Overviews. According to a May blog post from Google VP Liz Reid, weird results like this one stem from “data voids” where there is a little good content on a search, or where the only content is satirical, she explained.

“In a small number of cases, we have seen AI Overviews misinterpret language on webpages and present inaccurate information. We worked quickly to address these issues, either through improvements to our algorithms or through established processes to remove responses that don’t comply with our policies,” said Reid in the blog post.

Reid said that Google had introduced safeguards around AI Overviews to spot nonsensical queries and dial back the use of both humorous content and user-generated advice particularly around news and health topics. Google also added a warning label “Generative AI is experimental” after the launch of the AI summaries.

Google spokesperson Olivia O’Brien told Forbes in a statement: “The vast majority of AI Overviews are high quality, with their accuracy rate on par with other search features like Featured Snippets.”

Gunther’s back to competing at a gymnastics meet in Prague, Czechia, and said he’d be thrilled for his joke to live on in AI-powered infamy. “I hope in schools one day they will be teaching John Backflip,” joked Gunther.