How Brands Use Reddit to Poison AI Search

This week, we're doing a deep dive into how marketing companies are poisoning AI search results by manipulating Reddit. You may remember when Google’s AI search results first launched, it recommended that people put glue on their pizza. Well that happened because it scraped a 10 year old Reddit comment. We’ve learned over the last year or so that this sort of thing can be done on purpose, and brands are taking advantage of it. There’s been the rise of AEO or GEO, which stands for AI Engine Optimization or Generative Engine Optimization. Basically this is trying to get mentions of your brand into web content that’s likely to be scraped by AI tools. It’s the new version of SEO and lots of marketers and companies are trying to do it.

The most reliable, easiest way to do this appears to be by putting brand mentions onto Reddit. Reddit’s volunteer mods have noticed an increase in bot accounts and entire sequencing efforts—where a post and its comments are all basically done as a stealth ad—intended to boost brands. I wrote an article about this a few weeks ago, about r/biohackers banning mentions of peptides, which were a popular promoted class of product. After we wrote that article, researchers from Cornell University reached out to me about a new study they had just done.

The research is called “Deep-research agents can be poisoned via user-generated content,” which provides a mechanism for the ways reddit, wikipedia, and other sites that allow users to post are being attacked by brands doing AEO: "We show that a tiny snippet—just 13 words—of retrieved text on a UGC website like Reddit, Wikipedia, Quora, or Facebook can change AI agents to output spam / scam content pretty consistently," the study says.

We spoke to two of the researchers, Hal Triedman and Tingwei Zhang, about this problem and what, if anything can be done about it.

Deep-Research Agents Can Be Poisoned via User-Generated Content: https://arxiv.org/abs/2605.24245

Youtube Version: https://youtu.be/2uG8ohZHOD8

Learn more about your ad choices. Visit megaphone.fm/adchoices