Permissioned Data Shapes: Self-Only Bookmarks - Nick's Blog
A self-only space is the smallest shape permissioned data can take: one authority, one member, one repo, and private bookmarks that share a record shape and a write path with public ones.
The Atproto Spaces Alpha is Live - AT Protocol
Atproto Spaces, formerly known as “the permissioned data protocol,” is a new extension to atproto that enables non-public data. The alpha is now officially open. Here’s how to develop with it and what to expect as we work towards the full release.

Reintroducing Spaces - Daniel's Leaflets
Now with better perspective, zooming out and re-motivating the design of spaces, the new primitive for non-public data on atproto.
Permissioned Data Diary 1: To Encrypt or Not to Encrypt - Daniel's Leaflets
The first in a series of posts about major design decisions along the way to a permissioned data protocol for atproto.