What changed
OpenAI began rolling out Locked Chats, which removes selected conversations from history, pinned chats and search until the user supplies a four-digit PIN or device authentication. The feature is rolling out on web, iOS, Android and the new desktop app for Free, Go, Plus and Pro users.
Why it matters
The control reduces casual exposure of sensitive conversations on shared or briefly unattended devices without requiring users to delete the thread or move it outside ChatGPT.
What to do
Lock one non-critical conversation, confirm it disappears from history and search on every signed-in device, test recovery and sign-out behavior, and keep account security plus device encryption enabled because this is a visibility control rather than a separate retention boundary.
Caveat
OpenAI says locked chats keep the same retention and model-improvement settings as other chats. A local PIN or device-auth gate does not create a new enterprise access policy, export boundary or data-retention regime, and rollout may not have reached every account yet.