diff --git a/backend/app/api/ai_analysis.py b/backend/app/api/ai_analysis.py
index 3399936a..d80d369b 100644
--- a/backend/app/api/ai_analysis.py
+++ b/backend/app/api/ai_analysis.py
@@ -8,6 +8,7 @@ from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPIValue, KPIAlert, StrategicMap, User, ActionPlan, BudgetPlan, AISuggestion
 from app.utils.cache import get as cache_get, set as cache_set
+from app.utils.alert_entity_scope import month_period_clause
 import json, hashlib, httpx, os, urllib.request, urllib.parse
 from datetime import datetime, date
 router = APIRouter(prefix="/api/cma/ai", tags=["AI分析"],
@@ -102,6 +103,7 @@ def generate_rule_suggestions(db: Session, entity_id: int,
                 KPIValue.entity_id == entity_id,
                 KPIValue.entity_id.is_(None),
             ),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).first()
         if not latest or latest.actual_value is None:
             continue
@@ -286,7 +288,9 @@ async def dashboard_analysis(role: str = Query("ceo"), db: Session = Depends(get
                                           KPIDefinition.status == "active").all()
     kpi_summary = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         kpi_summary.append({
             "name": k.kpi_name,
             "code": k.kpi_code,
@@ -455,7 +459,9 @@ async def dashboard_analysis_stream(role: str = Query("ceo"), db: Session = Depe
     ).all()
     kpi_summary = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         kpi_summary.append({
             "name": k.kpi_name, "code": k.kpi_code, "dimension": k.dimension,
             "target": k.target_value, "actual": latest.actual_value if latest else None,
@@ -505,7 +511,9 @@ async def ask_question(
     ).all()
     kpi_context = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         alert = db.query(KPIAlert).filter(KPIAlert.kpi_id == k.id, KPIAlert.status == "pending").first()
         kpi_context.append(
             f"{k.kpi_name}({k.kpi_code}): 当前值={latest.actual_value if latest else '无'}"
@@ -573,7 +581,9 @@ async def review_plans(
     for p in plans:
         kpi = db.query(KPIDefinition).filter(KPIDefinition.id == p.kpi_id).first()
         kpi_name = kpi.kpi_name if kpi else "未知"
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == p.kpi_id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == p.kpi_id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         plan_text.append(
             f"- {p.title}\n"
             f"  关联KPI: {kpi_name}(当前值: {latest.actual_value if latest else '无'})\n"
diff --git a/backend/app/api/analysis_results.py b/backend/app/api/analysis_results.py
index 2646fe33..dbf4659c 100644
--- a/backend/app/api/analysis_results.py
+++ b/backend/app/api/analysis_results.py
@@ -20,6 +20,7 @@ from app.database import get_db
 from app.deps import get_entity_id
 from app.auth_middleware import require_auth
 from app.models import AnalysisResult, KPIValue, KPIDefinition, OperationLog
+from app.utils.alert_entity_scope import month_period_clause
 from typing import Optional, List
 from datetime import datetime
 
@@ -287,6 +288,7 @@ async def auto_calculate_confidence(
     # 查找历史数据（趋势）
     trend_values = db.query(KPIValue).filter(
         KPIValue.kpi_id == kpi.id,
+        month_period_clause(KPIValue.period),
     ).order_by(KPIValue.period.desc()).limit(6).all()
 
     has_actual = value is not None and value.actual_value is not None
diff --git a/backend/app/api/bi_reports.py b/backend/app/api/bi_reports.py
index 050b1625..c9dbb539 100644
--- a/backend/app/api/bi_reports.py
+++ b/backend/app/api/bi_reports.py
@@ -14,6 +14,7 @@ from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPIValue, BiReportTemplate, BiReport, OperationLog, KPICausality
 from app.utils.oplog import log_op
+from app.utils.alert_entity_scope import month_period_clause
 
 logger = logging.getLogger("bi-reports")
 
@@ -230,7 +231,7 @@ def analyze_data(data: dict, db: Session = Depends(get_db)):
         if period_end:
             val_query = val_query.filter(KPIValue.period <= period_end)
 
-        latest = val_query.order_by(KPIValue.period.desc()).first()
+        latest = val_query.filter(month_period_clause(KPIValue.period)).order_by(KPIValue.period.desc()).first()
 
         # 获取趋势数据
         trend_values = val_query.order_by(KPIValue.period.asc()).limit(12).all()
diff --git a/backend/app/api/bot_bridge.py b/backend/app/api/bot_bridge.py
index ac9ed024..c8bd3c1f 100644
--- a/backend/app/api/bot_bridge.py
+++ b/backend/app/api/bot_bridge.py
@@ -21,7 +21,7 @@ from app.models.cost_model import StandardCost, ActualCost, AbcActivity, AbcAllo
 from app.models import KPICausality
 from app.risk_levels import risk_level
 # 裁定 R1/R5（2026-09-19 财务口径）：demo 账套任何写通道不产生业务预警；期间非规整月不入库（单一事实源）
-from app.utils.alert_entity_scope import entity_alert_guard, guard_alert_period
+from app.utils.alert_entity_scope import entity_alert_guard, guard_alert_period, month_period_clause
 from app.utils.oplog import log_op, SCOPE_GLOBAL
 import json
 
@@ -135,7 +135,8 @@ def bot_kpis(
 
     results = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id)\
+        latest = db.query(KPIValue).filter(
+                KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period))\
             .order_by(KPIValue.period.desc()).first()
         results.append({
             "id": k.id, "name": k.kpi_name, "code": k.kpi_code,
@@ -166,7 +167,8 @@ def bot_kpi_history(
     kpi = db.query(KPIDefinition).filter(KPIDefinition.id == kpi_id).first()
     if not kpi or kpi.entity_id != entity_id:
         raise HTTPException(404, "KPI不存在")
-    values = db.query(KPIValue).filter(KPIValue.kpi_id == kpi_id)\
+    values = db.query(KPIValue).filter(
+            KPIValue.kpi_id == kpi_id, month_period_clause(KPIValue.period))\
         .order_by(KPIValue.period.desc()).limit(limit).all()
     return {
         "kpi": {"id": kpi.id, "name": kpi.kpi_name, "code": kpi.kpi_code, "unit": kpi.unit},
diff --git a/backend/app/api/bot_kpis.py b/backend/app/api/bot_kpis.py
index 4df5163b..151db227 100644
--- a/backend/app/api/bot_kpis.py
+++ b/backend/app/api/bot_kpis.py
@@ -8,6 +8,7 @@ from app.database import get_db
 from app.auth_middleware import require_auth
 from app.deps import get_entity_id
 from app.models import KPIDefinition, KPIValue
+from app.utils.alert_entity_scope import month_period_clause
 from app.risk_levels import risk_level
 
 router = APIRouter(prefix="/api/cma/bot-kpis", tags=["Bot KPI管理"],
@@ -88,6 +89,7 @@ def list_bot_kpis(
         )
         if period:
             val_query = val_query.filter(KPIValue.period == period)
+        val_query = val_query.filter(month_period_clause(KPIValue.period))
         latest_val = val_query.order_by(KPIValue.period.desc()).first()
 
         current_val = latest_val.actual_value if latest_val else None
diff --git a/backend/app/api/cash.py b/backend/app/api/cash.py
index fa9a082c..41940a75 100644
--- a/backend/app/api/cash.py
+++ b/backend/app/api/cash.py
@@ -12,6 +12,7 @@ from sqlalchemy import or_
 import pandas as pd
 from app.database import get_db
 from app.deps import get_entity_id, resolve_entity_for_request
+from app.utils.alert_entity_scope import month_period_clause
 from app.auth_middleware import require_role
 from app.models import CashPlan
 from app.utils.cash_forecast_engine import (
@@ -974,6 +975,7 @@ def _sync_cash_kpis(db: Session, entity_id: int, batch: str, periods: list) -> t
         dv = db.query(KPIValue).filter(
             KPIValue.kpi_id == debt_kpi.id,
             KPIValue.actual_value.isnot(None),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).first()
         if dv and dv.actual_value is not None:
             short_debt_wan = round(float(dv.actual_value) / 10000, 2)  # EXT_139单位元
diff --git a/backend/app/api/customer_dashboard.py b/backend/app/api/customer_dashboard.py
index 284fe0c9..ac8da0c7 100644
--- a/backend/app/api/customer_dashboard.py
+++ b/backend/app/api/customer_dashboard.py
@@ -8,6 +8,7 @@ from app.database import get_db
 from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPIValue, KPIAlert, User
+from app.utils.alert_entity_scope import month_period_clause
 import logging
 
 logger = logging.getLogger("cma.customer")
@@ -86,7 +87,7 @@ def list_customer_kpis(
             latest_val = sum(v.actual_value for v in values if v.actual_value) if values else None
             latest = type('obj', (object,), {"actual_value": latest_val, "period": f"{start_date}~{end_date}"})() if latest_val else None
         else:
-            latest = base_query.order_by(KPIValue.period.desc()).first()
+            latest = base_query.filter(month_period_clause(KPIValue.period)).order_by(KPIValue.period.desc()).first()
 
         # 最新预警
         alert = db.query(KPIAlert).filter(
@@ -127,6 +128,7 @@ def list_customer_kpis(
         # 最近6期趋势数据
         period_q = db.query(KPIValue).filter(
             KPIValue.kpi_id == k.id,
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).limit(6).all()
         period_values = [
             {"period": v.period, "value": v.actual_value}
@@ -171,6 +173,7 @@ def get_kpi_trend(
     # 获取最近N期数据
     values = db.query(KPIValue).filter(
         KPIValue.kpi_id == kpi_id,
+        month_period_clause(KPIValue.period),
     ).order_by(KPIValue.period.desc()).limit(months).all()
 
     trend_data = [
diff --git a/backend/app/api/dashboard.py b/backend/app/api/dashboard.py
index 60da5620..bff1af69 100644
--- a/backend/app/api/dashboard.py
+++ b/backend/app/api/dashboard.py
@@ -11,6 +11,7 @@ from app.models import KPIDefinition, KPIValue, KPIAlert, User, VoucherDetail
 from app.utils.cache import get as cache_get, set as cache_set
 from app.utils.voucher_guard import apply_voucher_guard
 from app.utils.threshold_parser import eval_threshold
+from app.utils.alert_entity_scope import month_period_clause
 # 指标方向（反向/正向）唯一权威源 = app.api.kpis.REVERSE_INDICATORS（2026-09-15 M2 准入2 收口）。
 # 本文件原自带一份字面量副本，与 kpis.py 漂移后会与「能力评分」判定相反，故改为导入。
 from app.api.kpis import REVERSE_INDICATORS
@@ -113,6 +114,7 @@ def get_bep_card(
             KPIValue.kpi_id == kpis[code].id,
             KPIValue.source_type == "derived",
             KPIValue.actual_value.isnot(None),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc(), KPIValue.id.desc()).first()
         latest[code] = {"period": v.period, "value": v.actual_value} if v else None
 
@@ -333,7 +335,7 @@ def get_dashboard_kpis(role: str = Query("ceo"), period: str = Query("month"),
             latest_val = sum(v.actual_value for v in values if v.actual_value) if values else None
             latest = type('obj', (object,), {"actual_value": latest_val, "period": f"{start_date}~{end_date}"})() if latest_val else None
         else:
-            latest = base_query.order_by(KPIValue.period.desc()).first()
+            latest = base_query.filter(month_period_clause(KPIValue.period)).order_by(KPIValue.period.desc()).first()
         
         alert = db.query(KPIAlert).filter(
             KPIAlert.kpi_id == k.id,
@@ -396,6 +398,7 @@ def get_my_kpis(
         
         trend_values = db.query(KPIValue).filter(
             KPIValue.kpi_id == k.id,
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).limit(6).all()
         trend = [{"period": v.period, "value": v.actual_value} for v in reversed(trend_values)]
         
@@ -446,6 +449,7 @@ def get_finance_analysis(
         
         trend_values = db.query(KPIValue).filter(
             KPIValue.kpi_id == k.id,
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).limit(6).all()
         trend = [{"period": v.period, "value": v.actual_value} for v in reversed(trend_values)]
         
@@ -578,7 +582,8 @@ def predict_kpis(db: Session = Depends(get_db), entity_id: int = Depends(get_ent
 # H1/H2/FY 等汇总期行，则回退到原按 calculated_at 的取法（不改变无月期 KPI 的行为）。
 # 注意：**不能**只按 period 字典序排 —— '2026-H1'/'2026-H2' 字典序大于 '2026-08'，会把
 # 季度汇总行/半年度预估值(forecast)当成"最新"。
-_MONTH_PERIOD_REGEX = r"^[0-9]{4}-(0[1-9]|1[0-2])$"
+# 期间口径（R3 正则 / SQL 等价式）已于 2026-09-26 收口到 app/utils/alert_entity_scope.py
+# （is_month_period / month_period_clause），此处不再保留第二份副本。
 
 # 主值优先（2026-09-18 同期间重复行判据收口，项目单 project-20260918-kpi-row-priority）
 # 同一期间可能并存两行：①主值（source_type='ledger' / data_status='verified'，结账/复核口径）
@@ -600,7 +605,7 @@ def latest_kpi_value(db: Session, kpi_id: int) -> Optional[KPIValue]:
     """该 KPI 的最新可用值：月期间优先（同期内主值优先），无月期间行时回退 calculated_at 倒序。"""
     monthly = (
         db.query(KPIValue)
-        .filter(KPIValue.kpi_id == kpi_id, KPIValue.period.op("REGEXP")(_MONTH_PERIOD_REGEX))
+        .filter(KPIValue.kpi_id == kpi_id, month_period_clause(KPIValue.period))
         .order_by(
             KPIValue.period.desc(),
             _MAIN_VALUE_PRIORITY,
diff --git a/backend/app/api/data_quality.py b/backend/app/api/data_quality.py
index ead77654..ee1f91aa 100644
--- a/backend/app/api/data_quality.py
+++ b/backend/app/api/data_quality.py
@@ -14,6 +14,7 @@ from app.deps import assert_entity_scope, get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPIValue, KpiDataQualityLog, OperationLog
 from app.api.kpis import kpi_to_dict
+from app.utils.alert_entity_scope import month_period_clause
 
 logger = logging.getLogger("data-quality")
 
@@ -74,6 +75,7 @@ def run_quality_check(db: Session = Depends(get_db), entity_id: int = Depends(ge
         values = db.query(KPIValue).filter(
             KPIValue.kpi_id == kpi.id,
             KPIValue.actual_value.isnot(None),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).limit(12).all()
 
         # 1. 检查数据缺失
@@ -365,6 +367,7 @@ def quality_stats(db: Session = Depends(get_db), entity_id: int = Depends(get_en
         latest_val = db.query(KPIValue).filter(
             KPIValue.kpi_id == kpi.id,
             KPIValue.actual_value.isnot(None),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).first()
         if latest_val and latest_val.calculated_at:
             if latest_val.calculated_at < stale_threshold:
diff --git a/backend/app/api/kpi_causality.py b/backend/app/api/kpi_causality.py
index 5f0ac85a..749a074a 100644
--- a/backend/app/api/kpi_causality.py
+++ b/backend/app/api/kpi_causality.py
@@ -13,6 +13,7 @@ from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPICausality, KPIValue, OperationLog
 from app.utils.oplog import log_op
+from app.utils.alert_entity_scope import month_period_clause
 from app.services.causality_verification import (
     ALL_STATUSES,
     ALL_SOURCE_TYPES,
@@ -147,7 +148,7 @@ def simulate_causality(data: dict, db: Session = Depends(get_db), entity_id: int
     )
     if period:
         query_values = query_values.filter(KPIValue.period == period)
-    latest = query_values.order_by(KPIValue.period.desc()).first()
+    latest = query_values.filter(month_period_clause(KPIValue.period)).order_by(KPIValue.period.desc()).first()
     if latest:
         current_value = latest.actual_value
 
@@ -188,6 +189,7 @@ def simulate_causality(data: dict, db: Session = Depends(get_db), entity_id: int
             tgt_val = db.query(KPIValue).filter(
                 KPIValue.kpi_id == target_id,
                 KPIValue.actual_value.isnot(None),
+                month_period_clause(KPIValue.period),
             ).order_by(KPIValue.period.desc()).first()
 
             predicted_value = None
diff --git a/backend/app/api/kpis.py b/backend/app/api/kpis.py
index 6db833f4..f4a77084 100644
--- a/backend/app/api/kpis.py
+++ b/backend/app/api/kpis.py
@@ -11,6 +11,7 @@ from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role, filter_kpis_by_role, kpi_visible_dims
 from app.models import StrategicMap, MapObjective, KPIDefinition, KPIValue, KPIAlert, OperationLog, Entity, KPICausality, KPIHierarchy, User
 from app.utils.oplog import log_op
+from app.utils.alert_entity_scope import month_period_clause
 from app.api.kpi_governance import validate_kpi_payload, kpi_issues_message
 from app.utils.threshold_parser import (
     calc_level as _tp_calc_level,
@@ -200,6 +201,7 @@ def get_kpi_score(
         )
         if period:
             val_query = val_query.filter(KPIValue.period == period)
+        val_query = val_query.filter(month_period_clause(KPIValue.period))
         latest_val = val_query.order_by(KPIValue.period.desc()).first()
 
         current_val = latest_val.actual_value if latest_val else None
@@ -291,6 +293,7 @@ def get_kpi_glossary(
         latest_val = db.query(KPIValue).filter(
             KPIValue.kpi_id == k.id,
             KPIValue.actual_value.isnot(None),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).first()
 
         current_value = latest_val.actual_value if latest_val else None
@@ -568,7 +571,9 @@ def list_kpi_values(
         raise HTTPException(404, "KPI不存在")
     if kpi.entity_id != entity_id:
         raise HTTPException(404, "KPI不存在")
-    vals = db.query(KPIValue).filter(KPIValue.kpi_id == kpi_id).order_by(KPIValue.period.desc()).all()
+    vals = db.query(KPIValue).filter(
+        KPIValue.kpi_id == kpi_id, month_period_clause(KPIValue.period)
+    ).order_by(KPIValue.period.desc()).all()
     return {
         "data": [{
             "id": v.id,
diff --git a/backend/app/api/predict.py b/backend/app/api/predict.py
index 87c26968..bfe3ce67 100644
--- a/backend/app/api/predict.py
+++ b/backend/app/api/predict.py
@@ -11,6 +11,7 @@ from app.utils.cash_forecast_engine import (
 )
 from app.database import get_db
 from app.deps import get_entity_id, resolve_entity_for_request, assert_entity_scope
+from app.utils.alert_entity_scope import month_period_clause
 from app.auth_middleware import require_auth_401
 from sqlalchemy.orm import Session
 
@@ -772,7 +773,7 @@ def _growth_quality_entity_from_db(db: Session, entity_id: int, period=None):
     )
     if period:
         q = q.filter(KPIValue.period == period)
-    rows = q.order_by(KPIValue.period.desc()).all()
+    rows = q.filter(month_period_clause(KPIValue.period)).order_by(KPIValue.period.desc()).all()
 
     entity = {"entity": ent.name}
     seen = set()
diff --git a/backend/app/api/reports.py b/backend/app/api/reports.py
index 22c84040..18adcf51 100644
--- a/backend/app/api/reports.py
+++ b/backend/app/api/reports.py
@@ -20,6 +20,7 @@ from app.database import get_db
 from app.auth_middleware import require_role, require_auth
 from app.models import KPIDefinition, KPIValue, BudgetPlan, StrategicMap, KPIAlert, User, Subject, ActionPlan, OperationLog, ReportHistory
 from app.utils.deviation_engine import calc_period_deviation, calc_period_diff, calc_deviation, get_budget_for_kpi
+from app.utils.alert_entity_scope import month_period_clause
 from app.utils.voucher_guard import apply_voucher_guard
 from app.services import report_reclass
 from app.deps import get_entity_id, assert_entity_slug_scope, resolve_session_slug
@@ -243,7 +244,8 @@ def get_kpi_trends(
     results = []
     for kpi in kpis:
         values = db.query(KPIValue).filter(
-            KPIValue.kpi_id == kpi.id
+            KPIValue.kpi_id == kpi.id,
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).limit(months).all()
         values.reverse()
 
@@ -2387,6 +2389,7 @@ def _fetch_kpi_data(db: Session, entity_id: int = 1) -> list:
         latest = db.query(KPIValue).filter(
             KPIValue.kpi_id == k.id,
             KPIValue.actual_value.isnot(None),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).first()
 
         alerts = db.query(KPIAlert).filter(
diff --git a/backend/app/api/subjects.py b/backend/app/api/subjects.py
index 3d10133a..4fd6e880 100644
--- a/backend/app/api/subjects.py
+++ b/backend/app/api/subjects.py
@@ -28,7 +28,9 @@ def list_subjects(
     账套分层（2026-09-23 `subjects` 加 `entity_id` 列）：返回**全局标准准则科目**
     （`entity_id IS NULL`）∪ **本账套私有明细**（`entity_id = 会话账套`）。
     行为变更（预期）：博海会话不再看到酣客智享通明细（`100106 酒窖备用金` / `100108 友赞商户` 等）。
-    返回体字段不删不加必填（前端契约不变）。
+    2026-09-26（yanxue-20260924-cma-fetch-caliber-fixes）：响应**增补 `entity_id`**
+    （`NULL` = 全局标准准则科目；`= 会话账套` = 本账套私有明细）——原响应不含该字段，
+    共享层（51 行）与酣客私有（156 行）在界面上不可区分。既有 10 个字段语义与名称不变。
     """
     query = db.query(Subject).filter(
         Subject.is_active == 1,
@@ -59,6 +61,7 @@ def list_subjects(
                 "new_standard_category": s.new_standard_category,
                 "is_active": s.is_active,
                 "remark": s.remark,
+                "entity_id": s.entity_id,
                 "updated_at": s.updated_at.isoformat() if s.updated_at else None,
             }
             for s in subjects
diff --git a/backend/app/services/knowledge_service.py b/backend/app/services/knowledge_service.py
index 57b7c498..ba690372 100644
--- a/backend/app/services/knowledge_service.py
+++ b/backend/app/services/knowledge_service.py
@@ -20,6 +20,7 @@ from sqlalchemy.orm import Session
 from sqlalchemy import func, and_
 
 from app.models import KnowledgeEvent, KnowledgeSummary, OperationLog, KPIAlert, KPIDefinition, KPIValue, UserEntity
+from app.utils.alert_entity_scope import month_period_clause
 
 logger = logging.getLogger("cma.knowledge")
 
@@ -165,7 +166,7 @@ async def _kpi_snapshot(db: Session, entity_id: int = 1) -> list[dict]:
     for k in kpis:
         latest = (
             db.query(KPIValue)
-            .filter(KPIValue.kpi_id == k.id)
+            .filter(KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period))
             .order_by(KPIValue.period.desc())
             .first()
         )
diff --git a/backend/app/utils/alert_entity_scope.py b/backend/app/utils/alert_entity_scope.py
index 3e20bf6e..00e6143e 100644
--- a/backend/app/utils/alert_entity_scope.py
+++ b/backend/app/utils/alert_entity_scope.py
@@ -87,6 +87,36 @@ def period_in_window(period, now: Optional[datetime] = None) -> bool:
     return str(period) >= window_lower_period(now)
 
 
+def month_period_clause(column):
+    """R3 的 SQL 等价式：`column` 必须落在规整月 `YYYY-MM`（供**取数层**查询使用）。
+
+    为什么取数层必须是 SQL 侧（而不是取完再在 Python 里挑）：
+      取数层的动作是「`ORDER BY period DESC` 取最新一行」（`.first()` / `.limit(N)`）。
+      伪期间 `2026-H2` 的**字符串序大于任何同年月份**（'H' > '0'），所以只要它留在排序里，
+      「最新实际期」就被它顶掉——取到的是**预测值/半年值**，而且 Python 侧再过滤也救不回来
+      （最新那一行已经不是月期间，第二行才是），`.first()` 的结果直接变成错值或空。
+      故本口径必须在 **SQL 侧**参与排序前的筛选。
+
+    跨库可移植：只用 `LENGTH` / `SUBSTR` / `BETWEEN` / `IN`（MySQL、SQLite、PostgreSQL 同名可用），
+    **不用 `REGEXP`**——SQLite 测试库未注册 REGEXP，SQL 侧正则会让单测与生产走两套语义。
+
+    与 Python 侧 `is_month_period` 同源等价：长度 7 + 第 5 位 `-` + 月份两位数字且 01–12
+    （`2026-13` 之类非法月同样排除）。禁止在调用点另写一份长度/正则判断。
+    """
+    from sqlalchemy import and_, func, or_  # 局部导入：本模块顶层不依赖 sqlalchemy 表达式 API
+
+    tens = func.substr(column, 6, 1)
+    ones = func.substr(column, 7, 1)
+    return and_(
+        func.length(column) == 7,
+        func.substr(column, 5, 1) == "-",
+        or_(
+            and_(tens == "0", ones.between("1", "9")),
+            and_(tens == "1", ones.in_(["0", "1", "2"])),
+        ),
+    )
+
+
 # ── 裁定 2b（2026-09-17）：「各 KPI 自己的最近可用期间」，单一实现 ──
 #
 # 2026-09-25（ASK-20260924-15）：原实现只在 `scripts/alert_generator.resolve_latest_period`，
diff --git a/backend/tests/test_period_caliber_actual_latest_20260926.py b/backend/tests/test_period_caliber_actual_latest_20260926.py
new file mode 100644
index 00000000..14a8cd67
--- /dev/null
+++ b/backend/tests/test_period_caliber_actual_latest_20260926.py
@@ -0,0 +1,189 @@
+# -*- coding: utf-8 -*-
+"""yanxue-20260924-cma-fetch-caliber-fixes-fullstack
+
+取数/接口层两处口径缺陷的回归用例（2026-09-26，wecom-fullstack）：
+
+1. **伪期间排序陷阱**：`kpi_values` 里的半年/预测伪期间（`2026-H2` 等）字符串序**大于**同年任何
+   月份（'H' > '0'）⇒ 任何 `ORDER BY period DESC` 取「最新值」的查询会命中伪期间，结论变成预测值。
+   本单把 R3 期间口径（仅 `YYYY-MM`）延伸到取数层：`app.utils.alert_entity_scope.month_period_clause()`。
+   改前本文件的前两个用例必红（返回 2026-H2 / -55.0）。
+2. **`GET /api/cma/subjects` 响应缺 `entity_id`**：共享层（`entity_id IS NULL`）与账套私有行
+   在界面上不可区分。本单只加字段，既有 10 个字段语义与名称不变。
+"""
+from datetime import datetime
+
+import pytest
+from fastapi.testclient import TestClient
+from sqlalchemy.orm import Session
+
+from tests.conftest import (
+    TEST_USER_PASSWORD, auth_header, create_test_kpi, create_test_user, get_token_for_user,
+)
+from app.models import Entity, KPIValue, Subject
+from app.utils.alert_entity_scope import is_month_period, month_period_clause
+
+GLOSSARY = "/api/cma/kpis/glossary"
+SUBJECTS = "/api/cma/subjects"
+
+# R3 判据样本：规整月 / 半年期 / 年期间 / 纯年份 / 非法月 / 近似格式
+# （`kpi_values.period` 为 NOT NULL，空值/None 由 is_month_period 直接断言，不入库）
+PERIOD_SAMPLES = [
+    "2026-08", "2026-09", "2026-01", "2026-12", "2025-12",
+    "2026-H1", "2026-H2", "2025-FY", "2026-Q2",
+    "2025", "2021", "2026-13", "2026-00", "2026-8", "2026-08-31",
+]
+
+
+def _mk_value(db: Session, kpi_id: int, period, value, entity_id: int = 1,
+              source_type: str = "manual", data_status: str = "verified") -> KPIValue:
+    v = KPIValue(entity_id=entity_id, kpi_id=kpi_id, period=period, actual_value=value,
+                 source_type=source_type, data_status=data_status)
+    db.add(v)
+    db.commit()
+    db.refresh(v)
+    return v
+
+
+def _token(client: TestClient, db: Session, entity_id: int = 1) -> str:
+    """按账套登录（1=酣客 / 2=博海）：确保企业存在 + 授权 + 取 token"""
+    from app.models import UserEntity
+
+    ent = db.query(Entity).filter(Entity.id == entity_id).first()
+    if not ent:
+        db.add(Entity(id=entity_id, name=f"企业{entity_id}", short_name=f"E{entity_id}", status="active"))
+        db.commit()
+    user = create_test_user(db)
+    if not db.query(UserEntity).filter(UserEntity.user_id == user.id,
+                                       UserEntity.entity_id == entity_id).first():
+        db.add(UserEntity(user_id=user.id, entity_id=entity_id))
+        db.commit()
+    return get_token_for_user(client, "testadmin", TEST_USER_PASSWORD)
+
+
+class TestMonthPeriodClause:
+    """SQL 等价式（取数层过滤）必须与 Python 侧 R3 判据逐值一致"""
+
+    def test_clause_equivalent_to_python_regex(self, db: Session):
+        kpi = create_test_kpi(db, kpi_code="T_PC_001")
+        for i, p in enumerate(PERIOD_SAMPLES):
+            _mk_value(db, kpi.id, p, float(i + 1))
+
+        rows = db.query(KPIValue.period).filter(
+            KPIValue.kpi_id == kpi.id, month_period_clause(KPIValue.period)
+        ).all()
+        sql_side = sorted(r[0] for r in rows)
+        py_side = sorted(p for p in PERIOD_SAMPLES if is_month_period(p))
+
+        assert sql_side == py_side, f"SQL 侧={sql_side} Python 侧={py_side}"
+        assert "2026-H2" not in sql_side and "2026-H1" not in sql_side
+        assert "2025-FY" not in sql_side and "2025" not in sql_side and "2026-13" not in sql_side
+        assert len(sql_side) == 5
+
+    def test_null_and_empty_are_not_month_periods(self):
+        """空值/None：Python 侧判据（列 NOT NULL，不入库）"""
+        assert is_month_period(None) is False
+        assert is_month_period("") is False
+        assert is_month_period(" 2026-08") is False
+
+
+class TestLatestActualPeriodOnFetchLayer:
+    """取数层「最新实际值」不得被伪期间顶掉（改前必红）"""
+
+    def test_glossary_current_value_skips_forecast_pseudo_period(self, client: TestClient, db: Session):
+        token = _token(client, db, 1)
+        kpi = create_test_kpi(db, kpi_code="F_NET_PROFIT", kpi_name="净利润", entity_id=1)
+        # 复刻生产证据（_evidence/hanke-data-gap-20260924/p11.out:56-57）
+        _mk_value(db, kpi.id, "2026-08", -10.46)
+        _mk_value(db, kpi.id, "2026-H1", -90.86)
+        _mk_value(db, kpi.id, "2026-H2", -55.0, source_type="forecast", data_status="estimated")
+
+        resp = client.get(GLOSSARY, headers=auth_header(token))
+        assert resp.status_code == 200, resp.text[:300]
+        item = [g for g in resp.json()["glossary"] if g["kpi_code"] == "F_NET_PROFIT"][0]
+
+        assert item["latest_period"] == "2026-08", f"latest_period={item['latest_period']}"
+        assert item["current_value"] == -10.46, f"current_value={item['current_value']}"
+
+    def test_glossary_kpi_with_only_pseudo_periods_has_no_current_value(self, client: TestClient, db: Session):
+        """只有伪期间数据 → 当前值必须是「无」，不得拿预测值/半年值充数"""
+        token = _token(client, db, 1)
+        kpi = create_test_kpi(db, kpi_code="T_PC_ONLY_PSEUDO", entity_id=1)
+        _mk_value(db, kpi.id, "2026-H2", 455.0, source_type="forecast", data_status="estimated")
+        _mk_value(db, kpi.id, "2026-H1", 713.27)
+
+        resp = client.get(GLOSSARY, headers=auth_header(token))
+        assert resp.status_code == 200, resp.text[:300]
+        item = [g for g in resp.json()["glossary"] if g["kpi_code"] == "T_PC_ONLY_PSEUDO"][0]
+
+        assert item["latest_period"] is None, f"latest_period={item['latest_period']}"
+        assert item["current_value"] is None, f"current_value={item['current_value']}"
+
+    def test_dashboard_latest_kpi_value_helper(self, db: Session):
+        """dashboard.latest_kpi_value（原 MySQL-only REGEXP，已收口到单一事实源）"""
+        from app.api.dashboard import latest_kpi_value
+
+        kpi = create_test_kpi(db, kpi_code="T_PC_HELPER")
+        _mk_value(db, kpi.id, "2026-06", 6.0)
+        _mk_value(db, kpi.id, "2026-H2", 99.0, source_type="forecast", data_status="estimated")
+
+        got = latest_kpi_value(db, kpi.id)
+        assert got is not None and got.period == "2026-06", f"period={getattr(got, 'period', None)}"
+        assert got.actual_value == 6.0
+
+
+class TestSubjectsEntityIdField:
+    """subjects 响应补 entity_id，既有 10 字段语义与名称不变"""
+
+    ORIGINAL_KEYS = {"id", "subject_code", "subject_name", "parent_code", "level", "category",
+                     "new_standard_category", "is_active", "remark", "updated_at"}
+
+    def _seed(self, db: Session):
+        db.add(Subject(entity_id=None, subject_code="1001", subject_name="库存现金",
+                       level=1, category="asset", is_active=1))
+        db.add(Subject(entity_id=1, subject_code="100106", subject_name="酒窖备用金",
+                       level=1, category="asset", is_active=1, remark="zxt-sync"))
+        db.add(Subject(entity_id=2, subject_code="100108", subject_name="友赞商户",
+                       level=1, category="asset", is_active=1, remark="zxt-sync"))
+        db.commit()
+
+    def test_response_contains_entity_id_and_keeps_original_fields(self, client: TestClient, db: Session):
+        token = _token(client, db, 1)
+        self._seed(db)
+
+        resp = client.get(SUBJECTS, headers=auth_header(token))
+        assert resp.status_code == 200, resp.text[:300]
+        data = resp.json()["data"]
+        assert data, "responses 为空"
+
+        for item in data:
+            assert self.ORIGINAL_KEYS.issubset(set(item.keys())), sorted(item.keys())
+            assert "entity_id" in item, sorted(item.keys())
+
+        by_code = {i["subject_code"]: i["entity_id"] for i in data}
+        assert by_code["1001"] is None          # 全局标准准则科目
+        assert by_code["100106"] == 1           # 会话账套（酣客）私有
+        assert "100108" not in by_code          # 他账套私有不可见（分层读取口径不变）
+
+    def test_bohai_session_sees_only_global(self, client: TestClient, db: Session):
+        self._seed(db)
+        ent = db.query(Entity).filter(Entity.id == 2).first()
+        if not ent:
+            db.add(Entity(id=2, name="企业2", short_name="E2", status="active"))
+            db.commit()
+        from app.models import UserEntity
+        user = create_test_user(db)
+        db.add(UserEntity(user_id=user.id, entity_id=2))
+        db.commit()
+        login = client.post("/api/cma/auth/login", json={
+            "username": "testadmin", "password": TEST_USER_PASSWORD, "entity_id": 2,
+        })
+        assert login.status_code == 200, login.text[:300]
+        token = login.json()["token"]
+
+        resp = client.get(SUBJECTS, headers=auth_header(token))
+        assert resp.status_code == 200, resp.text[:300]
+        data = resp.json()["data"]
+        by_code = {i["subject_code"]: i["entity_id"] for i in data}
+        assert by_code["1001"] is None
+        assert by_code["100108"] == 2
+        assert all(i["entity_id"] in (None, 2) for i in data)