Users and experts have uncovered a major privacy issue with Anthropic's Claude chatbot. Due to a technical error, private user conversations ended up in the databases of search engines Google and Bing, becoming accessible to the general public.
The situation came to light after Reddit users noticed that private conversations with the AI could be found via standard search. The problem stemmed from a feature allowing users to create public links to individual dialogues. When a user shared a "snapshot" of a chat, the system generated a separate page, which search bots subsequently discovered and added to their indexes.
Why robots.txt proved useless
Anthropic attempted to protect the data by instructing robots not to index shared chats using a robots.txt file. This directive prohibited data collection at least as early as September 2025. However, this measure proved insufficient to protect the pages.
Engineers from Google and Microsoft explained that a robots.txt file does not guarantee hiding if other websites link to the page. To fully block indexing, developers should have added a specific noindex tag to the page code or its header. Analysis shows that Anthropic failed to add this tag.
Google representative Ned Adrianse stated that responsibility for the public nature of pages lies solely with their owners. The search engine Bing displayed approximately 612 results for the query "site:claude.ai/share," confirming the scale of the leak.
Current status and risk of recurrence
Currently, most links have disappeared from Google search results; however, Claude pages still lack the noindex tag. This creates a risk of a repeated leak if links are shared online again.
Furthermore, developers at Anthropic, OpenAI, and Meta use instructions in robots.txt files to block competitor bots and prevent them from using their own data to train other AI models. However, as practice has shown, relying solely on this method to protect user data is dangerous.
Claude users can manually restrict access to their previously saved conversations in their account settings under Settings > Privacy > Shared chats.
