A post near the top of Hacker News has reminded people of something Google does not hide but does not advertise: paying for a personal Google AI plan does not stop Google using your saved Gemini chats to train its models. The policy applies to personal subscribers the same way it applies to free users, and for anyone who treats a paid plan as a privacy upgrade, that is the catch worth knowing.
The mechanics sit in Google's Gemini Apps privacy hub. If your Keep Activity setting is on, which is the default, your Gemini activity can be used to improve Google's services, including training its generative models. A subset of those chats is also read by human reviewers, who Google says help keep the product safe and improve it. Google's own guidance tells you not to enter confidential information you would not want a reviewer to see.
Deletion does not undo all of this. Google says ordinary activity auto-deletes after 18 months by default, a window you can shorten or extend. But chats that have been picked for human review are treated differently: they are disconnected from your account and kept for up to three years, and deleting your activity does not remove them. Google does say it does not sell this data and strips the account link before sending chats to reviewers.
The way out is to turn off Keep Activity or use temporary chats, neither of which is used to train Google's models. The trade-off is real. With activity off, chats are held for just 72 hours and the assistant loses the history that connected apps and personalised answers draw on, so you give up convenience for privacy. As we note in our Google Gemini review, the opposite promise sits behind the paywall: Gemini Enterprise, at $21 a seat, says customer data is not used for training. The same default-on training applies to free ChatGPT and consumer Claude, which we also review, where only the business tiers exclude training by default.
Two things are worth keeping in view. Google does not say how large the human-reviewed subset is, so the share of chats kept for three years is unknown. And the policy can change: this is Google's stated handling as of late October 2026, not a fixed guarantee. Anyone putting work or personal material into a personal Gemini account should turn activity saving off before, not after.