---
title: "Tag: CUI"
description: "1 blog entry tagged CUI, newest first, each with sealed and amended dates."
url: https://policycortex.com/blog/tags/cui
sealed: 2026-01-14
amended: 2026-01-14
register: blog/tags/cui
records: 3
digest: sha3:044e09af73db13d4488482d638bae7b314bdcecc71ee832766cf16ac18a42395
---

# Blog entries tagged CUI

Register / Blog / Tag: CUI

Every blog entry tagged CUI, newest first. Tags group the register by subject so a reader working one requirement can follow it across entries as the rules change. Each entry is sealed on the date shown and amended in place when it is updated; the full register is at the blog index.

1 entry · Latest sealed 2026-01-14

## Entries, newest first

| Sealed | Entry | Reading |
|---|---|---|
| 2026-01-14 | [NIST 800-171 Rev 3: Key Changes and How to Prepare](https://policycortex.com/blog/nist-800-171-rev-3-key-changes): NIST SP 800-171 Revision 3 brings significant changes to the security requirements for protecting CUI. | 2 min |

## Related records

Guides and articles describe the work. The evidence that work produces is described in three proof pages and one architecture page.

- **proof.state**: [Proof of State](https://policycortex.com/proof/state). What the environment was, as of a date someone else picks: point-in-time records, content hashed and chained.
- **proof.change**: [Proof of Change](https://policycortex.com/proof/change). Who or what altered the environment, under what authority, with before and after state hashes.
- **proof.agency**: [Proof of Agency](https://policycortex.com/proof/agency). What a machine was permitted to do before it acted, what it did, and what would have stopped it.
- **architecture**: [Architecture](https://policycortex.com/architecture). How the chain is built and where it lives: inside your tenant, with no egress of evidence.

Read the entries. Then verify the record they describe. [Request Access](https://app.policycortex.com/auth?mode=request-access) · [Book a call](https://policycortex.com/book)

## Register colophon

| Seq | Label | SHA3-256 | Prev |
|---|---|---|---|
| REC 0000 | HEAD | bb0ba38fa81d | 21850a37ad66 |
| REC 0001 | ENTRIES | a7e51303fc68 | bb0ba38fa81d |
| REC 0002 | RELATED RECORDS | 044e09af73db | a7e51303fc68 |

Head sha3:044e09af73db13d4488482d638bae7b314bdcecc71ee832766cf16ac18a42395. Each digest is SHA3-256 over the previous digest, the register key, the record label, and the record copy; a second party can recompute it from this document.