Group 1 - Perplexity, an AI search company, has announced the cessation of its advertising business, contrasting with the trend of other AI companies exploring ad monetization [1][2] - The decision to stop advertising is aimed at maintaining user trust in the search service, which is considered essential for enhancing user engagement and willingness to pay for services [2] - Perplexity's executives emphasized that advertising conflicts with the core user need for accurate and truthful answers, indicating a potential permanent halt to ad operations in the future [2] Group 2 - OpenAI has recently tested advertising features for some users, sparking discussions in the industry about monetization strategies for free consumer AI services [2] - Perplexity's advertising operations had been running for over a year, but concerns about the objectivity of search results led to the decision to phase out ads starting from the end of 2025 [2]