Reddit Faces a New Era of Spam: Brands Planting Fake Reviews to Feed AI Search
Product brands are posing as organic reviews on Reddit to get pulled into answers from ChatGPT and AI search, as research shows even a 13-word snippet can influence AI-generated responses
The Verge, reporting by Mia Sato, covered a new wave of spam on Reddit — one that is no longer just meant to deceive human readers, but to deceive "AI" as well. One example cited was a thread in a skincare subreddit, where a user asked whether anyone had tried a particular brand of hypochlorous acid spray (an antiseptic popularly used for acne). A user named Primary-Taro4254 then replied in an innocent-looking manner, recommending a spray from Honeydew Labs and detailing its benefits at length — a typical pattern of posing as a natural review to feed information to AI.
This phenomenon is known as "generative engine optimization," or GEO — a strategy of creating online content so that one's own brand appears in AI-generated answers. Forbes reported along the same lines that even as Reddit announced crackdowns on spam, bots, and inauthentic content, brands have been quietly using the platform to skew what AI search tools like ChatGPT say about them.
The concern is underscored by research from Cornell University, which found that a text snippet as short as 13 words embedded in a Reddit comment is enough to influence AI-generated answers, since modern language models frequently pull information from forums like Reddit to answer users' questions.
On Reddit's side, figures shared via TechCrunch show the company blocks 23 million spam viewing attempts per day and catches roughly 25,000 new spam posts and comments daily. It also stated that it reduced users' exposure to spam by 20% between January and March compared to the previous three months.
The impact is already visible at the community level. A report by 404 Media stated that moderators of r/biohackers recently announced restrictions on posts about peptides and hormone replacement, after discovering that companies selling those products were systematically inserting sponsored content so it would be picked up by tools like ChatGPT and Google AI search.
Many Thai people use ChatGPT or Google AI search to look up health information and product reviews. If those answers are seeded with fake brand reviews, users may unknowingly make purchasing decisions or use health products based on inauthentic information.