Auditable Commercial License (ACL) v1.0

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ACL · Version 1.0 · 2026

A source-available commercial license for the AI era.

Read, run, and modify the source internally. No redistribution, no hosted service. Every version becomes Apache 2.0 in four years — with the AI-training protection older commercial licenses were never built to address.

Three differences that matter

What makes this license different from the ones that came before it.

01 / AUDITABLE

Source available by right, not by favor.

Licensees may read, review, and audit the source code for security, compliance, and operational purposes — the rights enterprise buyers and regulated industries actually need, written in explicitly rather than implied.

02 / AI-PROTECTED

The clause the others forgot.

Section 2.3 prohibits use of the Licensed Work as AI training data, with a knowledge qualifier, a safe harbor for ordinary AI-tool use, and a flow-through obligation to AI vendors. The first commercially drafted clause built for the agent era.

03 / SELF-EXPIRING

Apache 2.0 in four years. Automatic.

Every released version automatically converts to the Apache License, Version 2.0 on the fourth anniversary of its public release. Adopters are never permanently dependent on the licensor's goodwill for any given version.

How it compares

Against the licenses you would otherwise reach for.

Apache 2.0 BUSL 1.1 Elastic 2.0 PolyForm ACL 1.0
Source available Yes Yes Yes Yes Yes
Blocks hosted-service competition No Yes Yes Partial Yes
AI training protection No No No No Yes
Auto-converts to OSI license N/A After 4y No No After 4y
Tier structure built in No No No No Yes
Enterprise IP indemnification No No No No Yes
Contributor patent grant Yes Partial Partial No Yes

Generate your license

Fill in five values. Download a license ready for counsel review.

Identity

The individual or entity that owns and distributes the Licensed Work.

Jurisdiction (Section 8.1)

City and state/country where courts have exclusive jurisdiction.

Notices (Section 8.7) — optional

Published separately on your website or README; not embedded in the license body by default.

Release metadata — for header & notice

Change Date is automatically set to four years after this date.

Live preview

Section 8.1 — Governing Law copy


        

Download your customized license Renders as LICENSE.md — drop it at the root of your repository.

The clause that defines it

Section 2.3 — the AI training clause.

Commercial source-available licenses were drafted for a world that didn't have autonomous code assistants. BUSL in 2017. Elastic 2.0 in 2021. None addresses the threat that now matters most — that the act of working with source code, using the tools developers actually use, quietly becomes an act of exfiltration into someone else's model.

This license addresses it. Three layers: a knowledge-qualified prohibition, a safe harbor for ordinary AI-tool use, and a flow-through obligation that reaches the vendor relationship without requiring surveillance.

The clause is not proprietary. Adopt it, adapt it, improve it. What matters is that the category has one — because every commercial license drafted in 2026 and 2027 will eventually need it, and the version that becomes standard will be the version written with the enforcement problem in mind.

Read the full essay on Substack →

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