ARIN puts ISP/LIR definitions and 4.10 in-region use into Last Call

What changed

ARIN's Advisory Council opened Last Call on two Recommended Draft Policies on 28 October 2026. Both windows close on 11 November 2026. Comments go to the Public Policy Mailing List.

• ARIN-2025-1, Clarify ISP and LIR Definitions and References. The draft clarifies the relationship between Local Internet Registry (LIR) and Internet Service Provider (ISP), adds an explicit ISP definition, and updates Number Resource Policy Manual text to use LIR consistently. Universities and other large enterprises that hold direct allocations should read how the revised wording describes their documentation duties.
• ARIN-2025-8, Reserve 4.10 Space for In-Region Use. Section 4.10 sets aside IPv4 allocations that facilitate IPv6 deployment. The draft would add “within the ARIN service area” to that dedication. ARIN's problem statement says staff already treat the section as limited to regional use; Last Call puts that boundary into policy text. Staff and legal review notes that allocations made before implementation are not intended to be reopened.

These two drafts were not rows in our September 2026 policy tracker. The out-of-region drafts that were, ARIN-2025-3 and ARIN-2026-5, remain Recommended Draft Policy and Draft Policy respectively on the drafts index checked on 10 November.

Why it matters for BYOIP teams

Section 4.10 space is a special IPv4 pool for IPv6 deployment work. A written in-region rule matters to anyone who had hoped to use that pool from a cloud region outside ARIN's service area. The ISP/LIR rewrite matters less for day-to-day BYOIP provisioning and more for how ARIN will read who must keep customer reassignment records.

What to check

• Whether you hold or plan to request a section 4.10 allocation, and where that space would be announced.
• Whether your organisation is described more clearly as an LIR under the revised definitions, and what documentation that implies.
• The Public Policy Mailing List before 11 November 2026 if you intend to comment.