diff --git a/backend/modules/audit/domain/event_type.go b/backend/modules/audit/domain/event_type.go
index f11defcc7..5f2861dc3 100644
--- a/backend/modules/audit/domain/event_type.go
+++ b/backend/modules/audit/domain/event_type.go
@@ -124,6 +124,10 @@ const (
 	TENANT_UPDATE_SUCCESS         ApplicationEventType = "TENANT_UPDATE_SUCCESS"
 	TENANT_TERMINATE_ATTEMPT      ApplicationEventType = "TENANT_TERMINATE_ATTEMPT"
 	TENANT_TERMINATE_SUCCESS      ApplicationEventType = "TENANT_TERMINATE_SUCCESS"
+	TENANT_REACTIVATE_ATTEMPT     ApplicationEventType = "TENANT_REACTIVATE_ATTEMPT"
+	TENANT_REACTIVATE_SUCCESS     ApplicationEventType = "TENANT_REACTIVATE_SUCCESS"
+	TENANT_PURGE_ATTEMPT          ApplicationEventType = "TENANT_PURGE_ATTEMPT"
+	TENANT_PURGE_SUCCESS          ApplicationEventType = "TENANT_PURGE_SUCCESS"
 	TENANT_SUPPORT_ACCESS_ATTEMPT ApplicationEventType = "TENANT_SUPPORT_ACCESS_ATTEMPT"
 	TENANT_SUPPORT_ACCESS_SUCCESS ApplicationEventType = "TENANT_SUPPORT_ACCESS_SUCCESS"
 
diff --git a/backend/pkg/eventstore/eventstore.go b/backend/pkg/eventstore/eventstore.go
index 8db642979..1727e786f 100644
--- a/backend/pkg/eventstore/eventstore.go
+++ b/backend/pkg/eventstore/eventstore.go
@@ -1,10 +1,13 @@
 package eventstore
 
 import (
+	"context"
+	"fmt"
 	"time"
 
 	chdriver "github.com/ClickHouse/clickhouse-go/v2"
 	"github.com/ClickHouse/clickhouse-go/v2/lib/driver"
+	"github.com/google/uuid"
 	"github.com/threatwinds/go-sdk/store"
 	"github.com/threatwinds/go-sdk/store/clickhouse"
 
@@ -69,4 +72,24 @@ func (s *Store) TableName(d store.Dataset) string {
 	return db + "." + name
 }
 
+// PurgeTenant deletes all rows scoped to the given tenant across every
+// dataset table. ClickHouse mutation, not synchronous — the ALTER returns
+// once accepted and the rows disappear as the mutation runs.
+//
+// tenantID must be a UUID string (caller passes uuid.UUID.String()); it is
+// inlined into the SQL because ClickHouse does not bind parameters inside
+// ALTER ... DELETE mutation expressions. The UUID shape makes inlining safe.
+func (s *Store) PurgeTenant(ctx context.Context, tenantID string) error {
+	if _, err := uuid.Parse(tenantID); err != nil {
+		return fmt.Errorf("purge: invalid tenant id: %w", err)
+	}
+	for _, d := range []store.Dataset{DatasetLogs, DatasetAlerts, DatasetStats} {
+		sql := fmt.Sprintf("ALTER TABLE %s DELETE WHERE tenantId = '%s'", s.TableName(d), tenantID)
+		if err := s.Conn.Exec(ctx, sql); err != nil {
+			return fmt.Errorf("purge %s: %w", d, err)
+		}
+	}
+	return nil
+}
+
 func SupportsTextSearch(d store.Dataset) bool { return d == DatasetLogs }