About BTCR

The Bitcoin Reference DID method (did:btcr) is designed as a minimal, secure, and open Decentralized Identifier (DID) method anchored to the Bitcoin blockchain. DIDs are an interoperable locator for identity that does not require permission from anyone else. The BTCR method specifically is fully open source — not tied to a commercial vendor — which makes it a valuable vendor-agnostic demonstration of the emerging DID specification.

Diagram of demonstrating BTCR DID Creation

Latest Updates

BIP-136 (TxRefs) merged

Most recently, BIP-136 was merged, allowing us to finalize BTCR identifier syntax. BIP-136 describes TxRefs, which are a standard, reliable, concise way to refer to a transaction position in the Bitcoin…

An important factor in the success of self-sovereign identity (SSI) has been the recognition that interoperability via open standards is essential. Contributors to this open ecosystem include huge players like Microsoft and IBM.

If you’re a fan of movies about the early PC wars (e.g. Pirates of Silicon Valley), it’s wonderful to see this sort of cooperation. SSI contributors/builders recognize that the stakes are extremely high with identity solutions.

Fortunately, non-tin-foil-hat wearing individuals are becoming increasingly aware of the problems caused by companies treating data irresponsibly…whether through honey-pot data leaks or 20-page EULAs that only increase opacity.

Marvin the Paranoid Android by david takes photos

In January I…

I’m excited to join the Decentralized Identity Foundation (DIF) steering committee on behalf of Learning Machine. To introduce myself and Learning Machine to the DIF community, I wanted to describe Learning Machine’s background/interest in decentralized identity (or, more specifically, self-sovereign identity) for ensuring an individual’s control over their data. I’ll highlight the initiatives Learning Machine is especially eager to champion at DIF, lending our experience and use cases from educational/occupational credentialing.

Learning Machine is deeply committed to recipient-centric credentialing. We incubated Blockcerts with MIT Media Lab in 2016 as an open source, open standard for creating, issuing, and verifying digital…

Lost in the World, Photo by Tobi Oluremi on Unsplash

Blockcerts, Decentralized Identifiers, and Verifiable Claims

Written by Kim Hamilton Duffy and Natalie Smolenski and presented at ePIC 2017 in Bologna Italy.


We are living through an historical moment in which momentum toward the unlimited collection and transferability of personal data by nation-states, industry leaders, and software providers is increasing irreversibly. Regulating this momentum from a policy standpoint will have at best limited effects so long as economic incentives and technological infrastructures collude to provide frictionless, one-way transparency into the lives of citizens, employees, customers, and learners. …

Kim Hamilton Duffy

Co-chair W3C Credentials Community Group, Researcher https://digitalcredentials.mit.edu, Decentralized identifiers, Verifiable Credentials, BTCR

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