diff --git a/internal/catalogd/subject.go b/internal/catalogd/subject.go
index 35e3e70..fbf8b65 100644
--- a/internal/catalogd/subject.go
+++ b/internal/catalogd/subject.go
@@ -37,19 +37,35 @@ const GenesisHash = "GENESIS"
 
 // SubjectManifest mirrors crates/shared/src/types.rs::SubjectManifest.
 // Keep field tags byte-identical so manifest JSON written by Rust round-trips.
+//
+// Vertical: omitempty matches Rust's serde-default deserializer accepting
+// missing field (default Unknown). For the OTHER fields we deliberately
+// avoid omitempty since Rust always emits them.
 type SubjectManifest struct {
-	Schema             string             `json:"schema"`
-	CandidateID        string             `json:"candidate_id"`
-	CreatedAt          time.Time          `json:"created_at"`
-	UpdatedAt          time.Time          `json:"updated_at"`
-	Status             string             `json:"status"`
-	Vertical           string             `json:"vertical,omitempty"`
-	Consent            SubjectConsent     `json:"consent"`
-	Retention          SubjectRetention   `json:"retention"`
-	Datasets           []SubjectDatasetRef `json:"datasets"`
-	SafeViews          []string           `json:"safe_views"`
-	AuditLogPath       string             `json:"audit_log_path"`
-	AuditLogChainRoot  string             `json:"audit_log_chain_root"`
+	Schema              string                `json:"schema"`
+	CandidateID         string                `json:"candidate_id"`
+	CreatedAt           time.Time             `json:"created_at"`
+	UpdatedAt           time.Time             `json:"updated_at"`
+	Status              string                `json:"status"`
+	Vertical            string                `json:"vertical,omitempty"`
+	Consent             SubjectConsent        `json:"consent"`
+	Retention           SubjectRetention      `json:"retention"`
+	Datasets            []SubjectDatasetRef   `json:"datasets"`
+	SafeViews           []string              `json:"safe_views"`
+	AuditLogPath        string                `json:"audit_log_path"`
+	AuditLogChainRoot   string                `json:"audit_log_chain_root"`
+	BiometricCollection *BiometricCollection  `json:"biometric_collection,omitempty"`
+}
+
+// BiometricCollection mirrors crates/shared/src/types.rs::BiometricCollection.
+// Written by the Phase 1.6 Gate 3 photo-upload endpoint. None until the
+// first biometric upload; cleared on BIPA erasure.
+type BiometricCollection struct {
+	DataPath            string          `json:"data_path"`
+	TemplateHash        string          `json:"template_hash"`
+	CollectedAt         time.Time       `json:"collected_at"`
+	ConsentVersionHash  string          `json:"consent_version_hash,omitempty"`
+	Classifications     json.RawMessage `json:"classifications,omitempty"`
 }
 
 type SubjectConsent struct {