3NUMLabs

Company

About 3NUM Labs

3NUM Labs is the engineering company behind ATSMS. We write the specifications, build the reference implementations and publish them under an open license, and we hold the accreditation root for the telephony layer until it can be handed to neutral governance. We are a builder of infrastructure, not a seller of phone service; the phone service built on our work is Haiven Mobile, a company we own and one operator among the many the protocol is designed for.

History

Where this came from

The company started in 2022 as ENUM, then 3NUM, after its founder was SIM-swapped and set out to make a phone number something a carrier employee could not hand to a stranger. The first answer was to bind numbers to identities on Ethereum: numbers you held with your own keys, encrypted messaging between them, and a bridge to the ordinary phone network. Those products shipped between 2022 and 2024 and are retired.

The idea carried over whole: a number should be bound to an identity that only its holder can speak for, and reaching everyone else should not mean giving that up. In 2025 the work moved to AT Protocol, leading with its existing identity methods, and was published as the open ATSMS protocol. What we built then under the name Bourbon is now the telephony layer of ATSMS. The articles from that period are still published here, kept as they were written.

  1. A SIM swap

    The founder's number is moved to a stranger's phone with one call to a carrier. The problem the company exists to solve.

  2. ENUM, then 3NUM

    Phone numbers bound to identities on Ethereum, with encrypted messaging between them. Backed by BlueYard, Notation, Acequia and A100x.

  3. 3NUM Shield, MobileKey, ENS Digits, Speak.3Z

    The first generation of products, and two Signal builds. All retired.

  4. ATSMS

    The work moves to AT Protocol and is published as an open protocol with a reference implementation. The telephony design is announced under the name Bourbon.

  5. Groups, calls, the first operator

    Encrypted group messaging with no server ordering anything, bridged calls from the phone network, and Haiven Mobile as the first operator on the stack.

Backed by

BlueYardNotation CapitalAcequia CapitalA100x

In the news

Coverage

Headlines are the outlets' own and are left as written. Most of this coverage is from the company's first generation of products.

Contact

[email protected] for everything: press, partnerships, operators, security (see security first), data requests.

Bluesky @3num.co · X @3numLabs · GitHub 3numlabs

Press boilerplate

3NUM Labs builds open infrastructure for private phone calls and messages. Its ATSMS protocol brings end-to-end encrypted messaging and calls to the AT Protocol identity people already have, with phone numbers bound to identities their holders control and gateways to the ordinary phone network. 3NUM Labs is the operating name of 3NUM Inc.