Mechanism
A biological identity in this disclosure is not a stored template but a trust-slope: a temporally ordered chain of biological hashes, each evaluated for continuity with its predecessors rather than matched against an enrolled reference. Lifecycle management is the function that keeps that chain operationally usable across the human lifespan. An identity health monitoring module continuously evaluates the structural health of each trust-slope and manages the trust-slope through establishment, maturation, active use, degradation, and potential reseeding. The disclosure draws an explicit distinction between identity validity and identity health: a trust-slope may be valid, in that its most recent validation event confirmed continuity, yet unhealthy, in that structural indicators suggest continuity validation is becoming unreliable. Lifecycle management acts on health before validity is lost.
This separation is what lets a single biological identity persist across decades of physiological change. Because each validation compares a new biological hash against the recent trajectory rather than a fixed enrollment template, gradual change is accommodated by the sliding window of recent trust-slope entries. Lifecycle management exists for the cases that the sliding window cannot absorb on its own: signals that have drifted far enough that the current stable sketch configuration no longer produces stable band assignments, evidence that has grown stale, and cryptographic parameters that have lived long enough to warrant rotation.
The Four Health Indicators
Identity health is assessed through four indicators disclosed in the specification. The first is staleness: the time elapsed since the most recent high-assurance validation event. A trust-slope that has not been refreshed by a high-assurance contact-based validation within the policy-defined freshness window is considered stale, because its accumulated confidence rests on aging evidence that may no longer reflect the individual's current biological state. The second is entropy trend: the trend in the variability of stable sketch band assignments over recent validation events. An increasing entropy trend indicates the individual's signals are becoming less stable, possibly because physiological change is degrading the discriminating power of the current stable sketch configuration.
The third indicator is continuity margin: the average margin by which recent validation events exceeded the minimum continuity threshold. A shrinking continuity margin indicates the trust-slope is approaching the boundary of valid continuity even though recent events have individually passed. The fourth is anchor freshness: the age of the most recent high-assurance anchor point in the trust-slope. High-assurance contact-based resolution events serve as anchor points because they produce the highest-quality captures and are validated against the strictest thresholds; their age is a direct measure of how recently the chain was reinforced by strong evidence. These four indicators look ahead to an impending continuity failure rather than reporting that one has already occurred.
Health Phases and Phase-Appropriate Action
From the four indicators the monitoring module assigns each trust-slope one of four health phases. A healthy trust-slope has all four indicators within acceptable ranges and requires no intervention beyond routine monitoring. A cautionary trust-slope has one or more indicators in warning ranges but remains operationally valid; it triggers recommended actions such as scheduling a high-assurance validation event or adjusting acceptance envelope parameters. A degraded trust-slope has indicators suggesting imminent continuity risk; it triggers mandatory actions, including requiring a high-assurance validation event within a policy-defined window and widening the continuity threshold to prevent premature continuity failure during the remediation period. A critical trust-slope requires immediate intervention to prevent continuity failure; it triggers suspension of capabilities bound to the trust-slope, a requirement for in-person re-validation, or initiation of the reseeding process.
The phases are operational states, not scores. Each phase names a concrete set of management actions, and the progression from healthy through critical is a progression from monitoring, to recommendation, to mandate, to intervention. The acceptance envelope referenced in the cautionary and degraded responses is the forward model of valid signal states disclosed elsewhere in the chapter; lifecycle management consumes it to decide whether widening tolerances or reseeding is the appropriate remedy for an observed drift.
Phase-Based Reseeding
Phase-based reseeding is the process by which a biological trust-slope is refreshed without breaking identity continuity. Reseeding replaces the trust-slope's stable sketch configuration, the projection vectors, the band boundaries, and the helper data, with a new configuration derived from the individual's current biological signals, while maintaining a cryptographic link between the old trust-slope and the new trust-slope that preserves the identity chain. It is triggered when the health monitoring module determines that the current stable sketch configuration has degraded beyond the point where continuity validation can be maintained reliably, for example when the individual's signals have drifted so far from the original configuration that band assignments are no longer stable.
The reseeding process requires a high-assurance contact-based validation event that does two things at once: it validates the individual's continuity with the old trust-slope and it establishes the root of the new trust-slope. The same event that confirms the individual is the legitimate continuation of the existing chain also seeds the replacement chain, and a cross-link is recorded that enables downstream systems to verify that the old and new trust-slopes represent the same biological identity. This is the structural reason re-enrollment is avoided: re-enrollment would create a new root disconnected from the prior identity history, whereas reseeding carries the cross-link that binds the new configuration to the accumulated chain.
Anchor Rotation
Anchor rotation is a scheduled variant of reseeding in which the trust-slope's cryptographic parameters, the salt values, the domain separation tags, and the helper data, are periodically refreshed without changing the stable sketch configuration. Where reseeding responds to biological drift by rebuilding the sketch, anchor rotation responds to cryptographic aging by refreshing keys and tags while leaving the sketch in place. It limits the window of vulnerability associated with any single set of cryptographic parameters and prevents long-term correlation analysis that might exploit the statistical properties of a long-lived hash chain.
Rotation is transparent to continuity validation. The rotated parameters produce different biological hashes from the same biological signals, but the validation process accommodates the change because the rotation is recorded in the trust-slope metadata and the comparison is adjusted accordingly. The individual experiences no discontinuity: the chain remains continuously valid across the rotation even though the raw hash values before and after the rotation differ.
Recovery From Continuity Failure
Lifecycle management also covers the case where continuity has already been lost. A continuity failure may result from physiological trauma or surgical intervention that abruptly changes the individual's signals, from extended absence that creates a trust-slope gap beyond the sparse validation tolerances, from sensor failure or compromise that corrupts trust-slope entries, or from detected anomalies that trigger trust-slope suspension as a security precaution. For these situations the disclosure provides quorum-based identity recovery, which preserves continuity by peer attestation rather than re-enrollment.
In recovery, the recovering individual presents a biological signal that the standard continuity validation cannot resolve because the trust-slope has been suspended or has failed. The system initiates a quorum process in which a policy-defined number of attesting peers, individuals whose own trust-slopes include a recorded association with the recovering individual's trust-slope, each independently validate against their own trust-slope and then provide a cryptographically signed forward continuity link attesting that they recognize the recovering individual as the same individual associated with the suspended trust-slope. When the required quorum of forward continuity links is obtained, the system re-establishes the trust-slope by creating a new root entry cryptographically linked to the prior trust-slope through the quorum attestations, preserving the identity chain across the discontinuity. The quorum policy includes anti-collusion safeguards: diversity requirements across relationship categories, temporal interaction periods, or organizational affiliations, and optional requirements that the attesting peers' own trust-slopes meet minimum age, cumulative confidence, and anchor freshness characteristics.
Revocation and Retention
The terminal lifecycle action is revocation. An individual may revoke a biological identity by instructing the system to invalidate the trust-slope associated with that identity within a specified domain. Revocation permanently invalidates the trust-slope: subsequent biological captures that would have been continuity-consistent with the revoked trust-slope are rejected, and capabilities bound to the revoked trust-slope are immediately invalidated. Revocation is domain-scoped by default, because the domain separation mechanism makes trust-slopes in different domains structurally independent; revoking an identity in one domain does not affect chains in other domains. Full revocation across all domains requires explicit invocation and is subject to governance approval to prevent accidental or coerced full revocation.
Retention is governed alongside revocation. A retention policy specifies how long trust-slope data, hashes, helper data, and metadata, is retained and under what conditions it is purged, and retention may vary by component: biological hashes may be retained for the lifetime of the identity while helper data may be retained only for the duration required to support the current stable sketch configuration. Because capability tokens are bound to the trust-slope and remain valid only while the trust-slope continues to validate with sufficient confidence, any lifecycle event that degrades or invalidates the chain, a failed validation, excessive sparsity, a detected anomaly, or revocation, automatically suspends or revokes the bound capabilities. Authorization is continuously re-evaluated rather than granted once and assumed indefinitely.
Disclosure Scope
Identity health monitoring, lifecycle management, and phase-based reseeding, comprising the four health indicators of staleness, entropy trend, continuity margin, and anchor freshness; the four health phases of healthy, cautionary, degraded, and critical with their phase-appropriate management actions; phase-based reseeding that refreshes the stable sketch configuration while preserving the identity chain through a high-assurance event and a cross-link; anchor rotation that refreshes cryptographic parameters without changing the sketch; quorum-based recovery through peer forward continuity links with anti-collusion diversity safeguards; and domain-scoped revocation with component-specific retention, is disclosed in the cognition filing (U.S. Application No. 19/647,395 and its international counterpart). This article describes that disclosed mechanism. The scope extends to long-horizon biometric identity for civil, medical, financial, and border-crossing contexts in which a single biological identity must remain operationally valid and cryptographically continuous across the human lifespan, including continuity maintained through abrupt physiological events that would otherwise force disconnected re-enrollment.
