Bitcoin Custody Standard

The Bitcoin Custody Standard (BCS) establishes a normative framework for evaluating and strengthening the resilience of Bitcoin custody architectures against Custodial Entropy over time. The Bitcoin Custody Resilience Index (BCRI) is the quantitative assessment instrument aligned with BCS, providing structured scoring across the five structural pillars. BCRI incorporates three headline metrics: Bitcoin Custody Resilience Index (BCRI): Structural resilience (0–100, higher is stronger) Entropy Risk Index (ERI): Time-based structural fragility (0–100, lower is better) Exposure Risk Index (XRI): Adversarial and visibility risk (0–100, lower is better) BCS is designed to operate alongside evolving institutional, regulatory, and technological custody frameworks while remaining structurally independent of jurisdiction-specific requirements.

The Bitcoin Custody Standard (BCS) establishes a normative framework for evaluating and strengthening the resilience of Bitcoin custody architectures against Custodial Entropy over time. Custodial Entropy is the inevitable structural degradation of custody systems over time due to forgotten knowledge, undocumented changes, technological evolution, shifting life circumstances, coordination complexity, and insufficient review. Because Bitcoin is a bearer asset with no recovery possible once keys are lost, BCS exists to reduce the probability that Bitcoin holdings become permanently inaccessible due to preventable Custodial Entropy. Bitcoin was introduced as a peer-to-peer electronic cash system in which ownership is defined exclusively by control of private keys, without reliance on centralized recovery authorities (Nakamoto, 2008). BCS operates within this foundational architectural constraint. BCS defines standardized terminology, structural domains, and conformance requirements to support consistent evaluation and long-term preservation of access across custody contexts. The Bitcoin Custody Resilience Index (BCRI) is the quantitative assessment instrument aligned with BCS. BCRI provides structured measurement and reporting across the five BCS structural pillars, including assessment of Entropy Risk through a proprietary Entropy Index. BCS defines the normative framework; BCRI operationalizes that framework through structured scoring and reporting.