The move marks one of the first significant examples of a social network’s charging for access to the conversations it hosts for the purpose of developing A.I. systems like ChatGPT, OpenAI’s popular program. Those new A.I. systems could one day lead to big businesses, but they aren’t likely to help companies like Reddit very much. In fact, they could be used to create competitors — automated duplicates to Reddit’s conversations.

Reddit’s move also comes as it prepares for a possible initial public offering on Wall Street later this year. The company, which was founded in 2005, makes most of its money through advertising and e-commerce transactions on its platform. Reddit said it was still ironing out the details of what it will charge for A.P.I. access and will announce prices in the coming weeks.

Reddit’s conversations — or subreddits, as the company calls them — have become valuable commodities as large language models, or L.L.M.s, have become an essential part of creating new A.I. technology.

L.L.M.s are essentially sophisticated algorithms developed by companies like Google and OpenAI, which is a close partner of Microsoft. To the algorithms, the Reddit conversations are data, and they are among the vast pool of material being fed into the L.L.M.s. to develop them.

The underlying algorithm that helped to build Bard, Google’s conversational A.I. service, is partially trained on Reddit data. OpenAI’s Chat GPT cites Reddit data as one of the sources of information it has been trained on.