By Muhammad Zulhusni
Publication Date: 2026-08-17 09:00:00
Perplexity has blocked advertising placed in AI-readable versions of Time’s webpages from influencing its search index, affecting an experiment that lets brands serve sponsored material directly to AI crawlers.
The AI search company confirmed the move after Time began placing ads inside markdown versions of its webpages that are intended for AI systems rather than human readers. Perplexity described the practice as deceptive advertising and warned that publishers using it risk a downgrade in its search index.
Time introduced the advertising format with adtech company Mobian. Ally Bank and the Project Management Institute (PMI) were among the brands testing it.
The ads appear in markdown versions of Time articles. Markdown provides a simplified, text-based version of a webpage with less visual formatting than the standard HTML page.
The sponsored material is structured as frequently asked questions containing information supplied and approved by advertisers and is labelled as sponsored content. The advertising does not appear on the standard webpages viewed by Time readers.
Testing reported by The Register found that AI crawlers including ClaudeBot, OAI-SearchBot, and PerplexityBot received versions containing sponsored content, while Google’s standard search crawler received the HTML presented to human visitors. The Register said it replicated the behaviour independently using a crawler simulation tool.
AI companies also use separate crawlers…