Licensing

Arc has two license paths, and neither path is implied by guesswork.

Choose the path before Arc becomes part of a product, device image, hosted service, SDK, or customer deliverable. The public path and the paid commercial path are separate choices for Arc-covered code; do not assume that starting on one path creates permission to ship on the other.

Public Arc Path

The public repository is licensed under AGPL-3.0-only.

Use this path when your firmware, service, or product workflow can satisfy the AGPLv3-only source, notice, and network-use obligations for Arc-covered code. If you distribute Arc-covered firmware or run modified network-accessible Arc-covered software, keep the corresponding Arc-covered source available under the same license terms.

The public path is suitable for projects that can carry reciprocal source-availability duties as a normal part of distribution or hosted use. It is not a quiet no-cost replacement for a proprietary embedded license.

Paid Arc Commercial Path

The commercial path is paid, written, and explicit.

Use this path only when the Arc copyright holder and the licensee sign a commercial agreement that names the licensed product, target hardware, scope, term, redistribution rights, and fees. Proprietary firmware distribution, private Arc modifications, private security handling, or terms that differ from AGPLv3-only exist only inside that signed agreement.

Cloning, building, embedding, linking, or distributing Arc from this repository does not create a commercial license.

Commercial eligibility also requires staying current on the fees, product scope, support term, field of use, and compliance duties in the signed agreement. If those conditions are not met, the repository grant falls back to AGPL-3.0-only.

Commercial Floor For Arc-Covered Code

A paid Arc license may relax the public AGPLv3-only path for the named product, but it must not make Arc disappear into a silent permissive dependency. Arc's commercial floor is:

• keep Arc notices intact;
• identify Arc in distributed products;
• track changes to Arc itself;
• preserve inspection or replacement rights for Arc-covered portions where the product architecture permits it;
• keep patent, anti-circumvention, and installation-information protections strong enough for the Arc-covered portion;
• keep rights limited to the products, targets, versions, and term named in the paid agreement.

Product And Feature Scope

A paid Arc agreement can cover proprietary firmware distribution, private source handling, private hardware-integration support, private security handling, warranty terms, or commercial-only deliverables. Those rights are bounded to the products, targets, versions, affiliates, users, and dates named in the signed agreement.

Arc does not currently ship a public commercial license key system. Any future license-key, entitlement, or enterprise-feature gate would be an enforcement mechanism for the signed commercial scope, not a separate permission by itself.

Third-Party Components

Arc builds on ESP-IDF and other upstream components selected through CMake. Those third-party components keep their own license terms. A paid Arc agreement does not rewrite upstream terms, and upstream permissive terms do not weaken Arc's AGPLv3-only public path for Arc-covered code.

Use THIRD_PARTY_NOTICES.md as the repository notice checklist before shipping a source archive, firmware image, SDK bundle, benchmark artifact, or documentation site that includes upstream material. Use THIRD_PARTY_MANIFEST.json and ./tools/third-party-manifest-check.py --format json when the release record needs a machine-readable dependency notice boundary. Use ./tools/sbom.py --format json when the release record also needs SPDX 2.3 SBOM evidence for Arc, external dependency groups, and locked docs npm packages. Use ./tools/license-policy-check.py --format json before publishing docs or evidence bundles so missing or unapproved npm package license declarations stop the release path.

The commercial license text in this repository is a policy statement, not an automatic grant. The signed agreement controls the actual commercial rights.

Decision Rule

Choose the public path when AGPLv3-only works for your product.

Choose the paid path before proprietary distribution, private Arc modification handling, or any deployment that cannot meet AGPLv3-only.

See COMMERCIAL-LICENSE.md for the repository-level commercial license path.