Reddit has become AEO's first spam battleground

For years, marketers added one word to a Google search when they wanted an answer that did not feel optimised: Reddit. Need an honest product recommendation? Add Reddit. Want to know whether a hotel is actually good? Add Reddit. That reputation for authentic human conversation has made Reddit extraordinarily valuable in the age of AI search. According to Semrush data provided to The Verge, Reddit was the most-cited domain in May across ChatGPT, Perplexity, Gemini and Google AI Mode — ahead of news publishers, scholarly repositories and Wikipedia. Marketers noticed. And now some are trying to game it.

<h2>From backlink spam to brand-mention spam</h2>

Traditional SEO created a simple incentive: if backlinks improved rankings, marketers found ways to manufacture backlinks. AI search creates a different incentive. If LLMs rely heavily on Reddit conversations when answering questions, then getting a brand mentioned positively on Reddit potentially influences what AI says. The optimisation target shifts from getting the link to getting the mention. The Verge reports that brands, agencies and startups are increasingly attempting to insert promotional content into Reddit discussions specifically because those conversations may subsequently influence AI-generated answers. That includes sock-puppet accounts, coordinated questions and apparently authentic product recommendations.

<h2>Why Reddit is such an attractive target</h2>

The underlying logic is straightforward. AI systems need evidence, and for some questions, corporate websites are not particularly persuasive. Ask what Nike says about Nike and the answer is predictable. Ask what running shoes actual runners recommend and Reddit becomes extremely useful. Thousands of communities contain years of detailed conversations between people discussing products, services and experiences in language that closely resembles the questions users now ask AI assistants. That makes Reddit an unusually rich source of what appears to be authentic human evidence — and therefore an unusually attractive target for manipulation.

<h2>The problem is bigger than Reddit</h2>

This is not fundamentally a Reddit problem. It is an evidence integrity problem. AEO is based partly on the idea that organisations can improve how AI systems understand them by improving the information environment those systems encounter. There is nothing inherently problematic about that: publishing better evidence, correcting inaccurate information, creating useful research, making factual claims clearer, earning credible third-party coverage. But deliberately manufacturing supposedly independent consumer opinion crosses a very different line. The distinction matters: improving the evidence environment is optimisation. Fabricating the evidence environment is manipulation.

<h2>AI makes the consequences different</h2>

Traditional spam generally attempted to fool an algorithm into ranking a page. AEO spam potentially attempts to influence something more consequential: what an AI system believes the evidence says. Imagine dozens of apparently independent Reddit users repeatedly describing a brand as the safest, the best value, recommended by professionals, superior to competitors. Those are not simply mentions — they are claims and associations. If AI systems repeatedly encounter them while gathering evidence, the concern is not merely whether the brand appears. It is whether manufactured consensus begins influencing how the system represents the brand.

<h2>Reddit is fighting back</h2>

Reddit moderators are already responding. The Verge documents communities banning suspected brand-affiliated accounts, removing covert promotional threads, filtering brand names and policing coordinated marketing activity. Reddit says its systems also block millions of spam views daily. The company is simultaneously introducing more sophisticated AI-assisted moderation — its new Rules Hub uses large language models to help interpret community rules and has already been piloted across more than 700 communities. There is considerable irony here: AI is helping marketers manipulate content intended to influence AI, while AI is also being deployed to detect the manipulation.

<h2>AEO Updates Takeaway</h2>

Search engines created economic value around rankings, and SEO followed. Then link farms, keyword stuffing and increasingly sophisticated manipulation followed. AI search is beginning to create economic value around citations, mentions and recommendations. AEO followed. Now manipulation is following too. The specific tactics are different; the incentive structure is not. The AEO industry needs its own norms — a clear distinction between making truthful information easier for AI systems to discover and manufacturing information designed to look independent so AI systems mistake marketing for evidence. The entire AI-search ecosystem depends on one scarce resource: trustworthy evidence. If marketers systematically contaminate the sources AI systems trust most, they do not just undermine Reddit. They undermine the credibility of AI answers themselves.

<h3>References</h3>

[1] The Verge — <a href='https://www.theverge.com' target='_blank' rel='noopener noreferrer'>Reddit spam and AI citation manipulation</a>