diff --git a/api/src/parser/statements/header.py b/api/src/parser/statements/header.py
index 6a061c2..d7c7aef 100644
--- a/api/src/parser/statements/header.py
+++ b/api/src/parser/statements/header.py
@@ -114,7 +114,7 @@ def _units(sheet: Sheet, rules: Rules, first_row: int, last_row: int) -> str | N
 
 def _report_date(
     sheet: Sheet, rules: Rules, block: FormBlock, first_row: int, last_row: int
-) -> tuple[str | None, "datetime.date | None"]:
+) -> tuple[str | None, datetime.date | None]:
     periods = rules.statement_periods
     if block.title_row is not None and block.title_row + 1 <= last_row:
         # Подзаголовок — только следующая строка за заголовком формы
diff --git a/api/tests/unit/parser/statements/test_header.py b/api/tests/unit/parser/statements/test_header.py
index 1641a00..a8e3f1e 100644
--- a/api/tests/unit/parser/statements/test_header.py
+++ b/api/tests/unit/parser/statements/test_header.py
@@ -7,7 +7,7 @@ from gridbuilder import at, sheet_from_rows
 
 from src.parser.rules import Rules, load_rules
 from src.parser.statements.detect import find_forms
-from src.parser.statements.header import _FULL_CONFIDENCE, parse_header
+from src.parser.statements.header import parse_header
 
 
 @pytest.fixture(scope="module")
@@ -63,7 +63,7 @@ def test_one_c_header(rules: Rules) -> None:
     assert header.units == "в тыс. рублей"
     assert header.report_date_text == "на 31 декабря 2024 г." and header.report_date == datetime.date(2024, 12, 31)
     assert header.address == "242440, Брянская обл, г Севск, ул Ленина, д. 130"
-    assert header.organization_name_confidence == _FULL_CONFIDENCE and header.inn_confidence == _FULL_CONFIDENCE
+    assert header.organization_name_confidence == 100 and header.inn_confidence == 100  # noqa: PLR2004
     assert warnings == []
 
 
@@ -163,3 +163,63 @@ def test_inn_skips_auditor_block(rules: Rules) -> None:
     header, _ = parse_header(sheet, rules, 1, 16, _block(sheet, rules))
     assert header.inn == "3249004697", f"Expected organization INN 3249004697, got {header.inn}"
     assert header.inn != "7716021332", "Auditor INN 7716021332 should not be included"
+
+
+def test_inn_from_auditor_block_only_is_none(rules: Rules) -> None:
+    """Guard test (a): without org INN, only auditor block ИНН — should be None."""
+    sheet = sheet_from_rows(
+        [
+            [*at({3: "Отчет о финансовых результатах"})],
+            [*at({3: "за январь - сентябрь 2025 г."})],
+            [*at({13: "Форма по ОКУД", 14: "0710002"})],
+            [*at({7: 'ООО "ПРОКАТНЫЙ ЗАВОД"'})],
+            [*at({3: "Организация:", 13: "по ОКПО", 14: "16098811"})],
+            [*at({3: "Единица измерения", 8: "тыс. руб.", 13: "по ОКЕИ", 14: "384"})],
+            [*at({2: "Наименование аудиторской организации"})],
+            [*at({2: 'АО "АУДИТ-КОМПАНИЯ"'})],
+            [
+                *at({
+                    2: "Идентификационный номер налогоплательщика аудиторской организации",
+                    33: "ИНН",
+                    34: "9999999999",
+                })
+            ],
+        ]
+    )
+
+    header, _ = parse_header(sheet, rules, 1, 9, _block(sheet, rules))
+
+    assert header.inn is None, f"Should not pick up auditor INN 9999999999, got {header.inn}"
+
+
+def test_inn_from_auditor_above_organization_inn_line(rules: Rules) -> None:
+    """Guard test (b): org INN before auditor block; guard excludes auditor INN.
+
+    Organization section (rows 1-4) has INN 1234567890.
+    Auditor block starts at row 5 and has INN 7716021332.
+    Guard searches up to row 4, finds org INN.
+    """
+    sheet = sheet_from_rows(
+        [
+            [*at({3: "Бухгалтерский баланс"})],
+            [*at({3: "на 31 декабря 2024 г."})],
+            [*at({7: 'ООО "ЗАВОД"'})],
+            [*at({2: "Идентификационный номер налогоплательщика", 33: "ИНН", 34: "1234567890"})],
+            [*at({2: "Наименование аудиторской организации"})],
+            [*at({2: 'АО "ЮНИКОН"'})],
+            [
+                *at({
+                    2: "Идентификационный номер налогоплательщика аудиторской организации",
+                    33: "ИНН",
+                    34: "7716021332",
+                })
+            ],
+            [*at({2: "Единица измерения", 7: "в тыс. рублей", 33: "по ОКЕИ", 34: "384"})],
+        ]
+    )
+
+    header, _ = parse_header(sheet, rules, 1, 8, _block(sheet, rules))
+
+    assert (
+        header.inn == "1234567890"
+    ), f"Should pick organization INN 1234567890, not auditor INN 7716021332, got {header.inn}"