Bitcoin Custody Standard

The First Structural Benchmark for Bitcoin Custody

An independent framework for evaluating Bitcoin custody architecture.

Not a wallet. Not a custodian. Not affiliated with any provider.

The standard evaluates whether a custody system remains recoverable across time, custodial entropy, exposure, and coordination.

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Resilience Efficiency Frontier
No Sovereignty Single-Key Collaborative Distributed Institutional
No Sov. Single-Key Collaborative Distributed Institutional 0 10 20 30 0 2 4 6 8 10 Complexity Score (CS) ERE Peak CS 4.5

The Resilience Efficiency Frontier shows how custody architectures perform relative to their structural complexity. It provides a benchmark view of where resilience becomes efficient — and where added complexity begins to produce diminishing returns.

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Standard Normative Summary → Benchmark BCRI Benchmark Report → Research Research Archive → Glossary Definitions → Governance Governance →
About the Standard

Custody is evaluated as a structural system—not a product or device choice. The framework asks whether an architecture can preserve control across time, operational change, participant turnover, and adversarial conditions.

The framework introduces custodial entropy: the gradual degradation of a system through knowledge loss, coordination drift, undocumented change, and unmaintained processes.

BCRI Structural Model

All custody evaluation flows through this model. Hover any node for its definition — click to pin.

Five Structural Pillars

Custody resilience is evaluated across five independent structural domains:

Cryptographic Integrity
Key generation, material handling, derivation path preservation, algorithmic resilience.
Physical Distribution
Geographic redundancy of recovery material across independent risk domains.
Operational Dependency
Reliance on devices, software, providers. Portability is a core requirement.
Cognitive Reliability
Recovery must not depend on memory. Procedures must be documented.
Temporal Resilience
Long-horizon survivability through review, succession planning, entropy mitigation.
Measurement Components

These pillars feed into four measurable components, which are combined into a composite resilience assessment:

ARS
Architecture Resilience Score
Structural strength across the five pillars. 0–100, higher is stronger.
ERI
Entropy Risk Index
Long-horizon degradation of custody reliability over time. Comprises Latent Entropy (LEI) and Coordination Entropy (CEI). 0–100, lower is better.
XRI
Exposure Risk Index
How identifiable, targetable, and attackable the custody system is under adversarial conditions. 0–100, lower is better.
CHS
Coordination Health Score
Reliability of coordination required to execute transactions and recovery across participants over time. 0–100, higher is stronger.
BCRI
Bitcoin Custody Resilience Index
Score (0–100) · Rating (AAA–D)
BCRI = f(​ARS, ERI, XRI, CHS)
Outputs
BCRI Score
Composite resilience score from 0 to 100.
BCRI Rating
Standardized resilience classification.
Frontier Positioning
Placement relative to the resilience efficiency frontier.
Resilience Gap Analysis
Identification of structural weaknesses in the current architecture.
Resilience Upgrade Path
Targeted improvements to increase resilience.
Core Publications

The framework is published through three core documents:

BCS-NS-1.1 · Normative Standard
BCS-NS-1.1 — Normative Standard

Defines the public normative framework of the Bitcoin Custody Standard, including the structural basis for evaluating Bitcoin custody resilience across time.

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BCS-BR-1.0 · Benchmark Report
BCS-BR-1.0 — BCRI Benchmark Report

Applies the Bitcoin Custody Standard framework across benchmark custody architectures to evaluate structural resilience and operational complexity.

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BCS-RE-1.0 · Research Archive
BCS-RE-1.0 — Research Archive

Ongoing research papers and analytical publications expanding the Bitcoin Custody Standard across specific custody architectures, failure modes, and operational questions.

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Application and Evaluation

The scoring methodology is maintained as a controlled model to ensure consistency, comparability, and integrity across assessments.

Evaluations are conducted under the Bitcoin Custody Standard framework and administered by the Bitcoin Custody Standard Initiative.

The standard is version-controlled, with benchmark and research publications expanding over time.