A “Tell HN” post on Hacker News titled “Gemini trains on chat history, even for subscribers (personal accounts)” had 536 points and 137 comments when Lens checked on November 4, 2026. The post’s author, who posts as jameslk, says that with a personal Google AI subscription, saved chat history in Gemini can be used for training, and that the only opt-outs are turning off chat history or using temporary chats. Lens compared the post with Google’s Gemini Apps Privacy Hub, which the page says was last updated on October 26, 2026.

What the post says

  • It says that with a personal Google AI subscription, all saved chat history in Gemini can be used for training.
  • To stop that, the author says, you must turn off “Keep Activity,” which also drops chat sessions after 72 hours, or use temporary chats.
  • The author says they assumed a paid plan would keep them out of training and learned otherwise too late.
  • The author quotes Google’s help page: “A subset of chats are reviewed by human reviewers,” and its warning not to enter confidential information.

What Google’s help page says

The passages below are from Google’s Gemini Apps Privacy Hub, read by Lens on November 4, 2026.

  • Keep Activity on: chats and what a user shares with Gemini are saved in their Activity, and “Google uses your activity to provide, develop, and improve its services,” including Gemini models and other generative AI models, according to the page.
  • Keep Activity off: future chats “won’t appear in your Activity, and won’t be used to train our AI models, unless you choose to send Google feedback.” Chats are still saved for 72 hours so Gemini can respond, process feedback and protect Google, its users and the public.
  • Temporary chats: retained for 72 hours and “not used to train Google’s AI models.”
  • Human review: a subset of chats is reviewed by human reviewers, including Google’s trained service providers, to improve Google services and to keep Gemini safe and secure. The page says reviewers assess whether responses were low-quality, inaccurate or harmful and suggest better responses. It also says, “Please don’t enter confidential information that you wouldn’t want a reviewer to see or Google to use to improve our services.”
  • Retention of reviewed chats: if a user deletes their activity, past chats already reviewed by service providers are not deleted, because they are not connected to the user’s Google Account; they are retained for up to three years.
  • Subscriptions: the page lists subscription information among the data collected, with the line “if you have a paid subscription to a Google AI plan, subscription related information.” The word “paid” appears once on the page, in that line, and Lens did not find a passage that treats paid and free personal accounts differently for training.
  • Work and school accounts: the page says use of Gemini Apps with a work or school Google Account may be subject to different data handling terms and points to a separate Workspace privacy hub.

What commenters said

Comments on the thread, as Lens read them, included a user who said frontier model providers may have human reviewers reading chats even when activity tracking is disabled, one who said Gemini reminders on a Pixel phone stopped working with chat history off, and others who described a similar “all or nothing” pattern across Google apps. Some argued that the human review and three-year retention are likely for legal and safety reasons, while others replied that the purposes Google states are broader. These are individual commenters’ views, not verified findings.

Sources and notes

This post is based on the Hacker News thread (author jameslk, 536 points and 137 comments when read; the page showed “9 hours ago” rather than a date) and Google’s Gemini Apps Privacy Hub (last updated October 26, 2026; the privacy notice itself is dated October 13, 2026). Lens did not test any account settings or confirm what happens to any user’s chats, and did not find a response from Google to the thread. The thread’s claim about paid personal accounts is the author’s; Google’s page, as read by Lens, does not state it either way. Lens did not contact Google.

Image: a smartphone in a folio case lying on a wooden table, by Santeri Viinamäki via Wikimedia Commons, licensed under CC BY-SA 4.0; cropped. Stand-in photo; the screen is not visible and it shows no Gemini interface or the events described.