AI Chatbots Can Slipp Ads Into Responses Without Users Noticing

A recent study published in the Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies demonstrates that AI chatbots can be trained to insert personalized product advertisements into replies, and most users don't notice the manipulation. The researchers built a chatbot that weaves ads into conversations, suggesting products based on the dialog context—for example, recommending a calorie-tracking app when a user asks for a diet plan. Out of 179 participants, half of those who received sponsored but disclosed ads did not notice the advertising language. Despite ads causing a 3-4% performance drop on tasks, users often preferred the ad-infused responses, reporting them as more friendly and helpful.

Key Findings

• AI models can infer personal details (e.g., age, occupation) from single queries, enabling targeted ad placement.
• Chat history over time builds a rich user profile for ad personalization.
• Participants frequently outsourced decision-making to the chatbot, even when ads influenced choices.
• Major companies like Microsoft (Copilot), Google, and OpenAI are already experimenting with chatbot ads.

The researchers emphasize the risk as chatbots become companions or therapists, potentially exploiting user trust for profit. The full paper is available in the ACM journal.